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Soru 4841Soru →

In a socialist command economy, state planners reallocate productive resources to consumer goods and fix official retail prices below their market-clearing levels. If state enterprise managers are evaluated strictly on meeting physical output targets rather than profitability, what is the direct impact on resource allocation and consumer satisfaction?

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Cevap: Consumer preferences remain secondary, resulting in persistent product shortages and non-price rationing.

Cevap

Consumer preferences remain secondary, resulting in persistent product shortages and non-price rationing.
In a command (socialist) economy, central planning authorities determine resource allocation, production targets, and price levels. When retail prices are artificially fixed below market-clearing equilibrium and managers are rewarded for volume rather than profitability, the economy lacks dynamic price signals to adjust output. Consequently, consumer sovereignty is ignored, resulting in chronic market shortages and non-price rationing such as queues.

Adım Adım Çözüm

1
Identify the primary mechanism for resource allocation in a command economy.
Production decisions and prices are set by central government planners rather than through market forces.
Public ownership of the means of production eliminates the profit motive and free market price signals.
2
Analyze the effect of administrative price fixing below market-clearing levels.
Prices cannot fluctuate to clear the market, leading to excess demand (shortages) and rationing mechanisms like queuing.
Enterprise managers focus on fulfillment of state-mandated physical units rather than responding to consumer sovereignty.

Anahtar Kavram

Central Planning and Resource Allocation in Command Economies
Soru 4842Soru →

An animal specimen collected during a field study is triploblastic, unsegmented, possesses a pseudocoelom, and has a complete digestive tract with both a mouth and an anus. To which phylum does this organism belong?

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Cevap: Nematoda

Cevap

Nematoda
The correct answer identifies Nematoda because roundworms are characteristically triploblastic, unsegmented, possess a pseudocoelom derived from the blastocoel, and have a complete digestive tract featuring both a mouth and an anus.

Adım Adım Çözüm

1
Analyze the structural characteristics described in the question stem.
The organism is triploblastic (three germ layers), unsegmented, has a pseudocoelom (false body cavity), and features a complete digestive system (mouth and anus).
Identifying diagnostic anatomical features allows precise classification into the correct lower invertebrate phylum.
2
Compare the features against the characteristics of lower invertebrate phyla.
Porifera lack true tissues. Coelenterata are diploblastic with an incomplete gut. Platyhelminthes are triploblastic but acoelomate with an incomplete gut. Nematoda possess three germ layers, a pseudocoelom, and a complete gut.
The presence of a pseudocoelom combined with a alimentary canal having separate oral and anal openings is unique to Nematoda among the listed lower invertebrate groups.

Anahtar Kavram

Body plan and structural characteristics distinguishing lower invertebrate phyla (Porifera, Coelenterata, Platyhelminthes, and Nematoda)
Tahmini Süre:1m 0s
Soru 4843Soru →

In national income accounting, non-monetized activities such as unpaid housework performed by family members are included in official Gross Domestic Product (GDP) calculations.

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Cevap: False

Cevap

The statement is False. Unpaid household services and non-monetized activities are excluded from Gross Domestic Product (GDP) estimations because no money changes hands, creating a major practical difficulty in measuring total national output.
Unpaid domestic work does not enter the market mechanism, so no prices or transactional data exist to measure its value. Consequently, statistical agencies omit these non-monetized activities, which remains a primary conceptual and practical problem in national income measurement.

Adım Adım Çözüm

1
Examine the role of non-monetized household activities in economic accounting.
Unpaid housework generates utility and productive output but lacks a market price.
National income accounting depends primarily on recorded monetary transactions in organized markets.
2
Determine if non-market domestic activities are included in official GDP statistics.
They are omitted from official national income figures.
The absence of transaction receipts makes calculating an accurate monetary valuation extremely difficult.

Anahtar Kavram

Exclusion of Non-Monetized Transactions
Tahmini Süre:45s
Soru 4844Soru →

In Nigeria's agricultural sector, cattle rearing simultaneously yields beef and hides, whereas raw cassava tubers can be processed into either garri or industrial starch. If an expansion in livestock farming occurs alongside a major shift by processors toward industrial starch production, what will be the effect on the market supply of hides and garri?

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Cevap: The supply of hides will increase, while the supply of garri will decrease.

Cevap

The supply of hides will increase, while the supply of garri will decrease.
Beef and hides are by-products of cattle rearing, meaning they are in joint (complementary) supply; expanding livestock production inherently increases hide availability. On the other hand, garri and industrial starch rely on cassava as a shared input, placing them in competitive supply; diverting cassava toward starch manufacturing reduces the raw materials available for garri, shifting the supply curve of garri to the left (decrease in supply).

Adım Adım Çözüm

1
Identify the type of supply relationship between beef and hides.
Beef and hides are produced together from cattle rearing, making them joint (complementary) supply goods.
An increase in cattle production automatically leads to an increase in the output of both beef and hides.
2
Identify the type of supply relationship between garri and industrial starch.
Garri and industrial starch compete for the same raw material (cassava), making them competitive supply goods.
Because the supply of raw cassava is finite, increasing the quantity allocated to industrial starch leaves less cassava available for garri processing.
3
Synthesize the simultaneous market effects.
Increased cattle farming shifts the supply curve of hides to the right (increase in supply), while reallocation of cassava to starch shifts the supply curve of garri to the left (decrease in supply).
Joint supply leads to parallel movement with primary production, whereas competitive supply creates an inverse production relationship between competing final uses.

Anahtar Kavram

Distinguishing between Joint (Complementary) Supply and Competitive Supply
Tahmini Süre:2m 0s
Soru 4845Soru →

In a population of moths inhabiting an industrial region, dark-colored individuals became significantly more common over several generations as pollution darkened the tree trunks. According to Charles Darwin's theory of natural selection, which mechanism best accounts for this change in the population?

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Cevap: Pre-existing dark genetic variations provided a camouflage advantage against predators, resulting in higher survival and reproduction rates for dark moths.

Cevap

Pre-existing dark genetic variations provided a camouflage advantage against predators, resulting in higher survival and reproduction rates for dark moths.
According to Darwin's theory of natural selection, populations contain natural genetic variations. When the environment changed due to industrial pollution, dark moths gained a camouflage advantage. They were preyed upon less frequently by birds, allowing them to survive and pass their dark-pigment genes to the next generation at higher rates.

Adım Adım Çözüm

1
Identify the foundation of Darwinian evolution.
Natural selection requires inherited genetic variation to already exist within a population prior to environmental change.
Organisms do not generate intentional phenotypic changes within their lifetime to suit new environments.
2
Analyze the environmental selective pressure.
Soot-covered trees made dark moths less visible to predators compared to light-colored moths.
Selective pressures determine which existing phenotypes offer a survival advantage.
3
Determine the population-level outcome.
Darker moths survived longer and produced more offspring, increasing the proportion of dark moths in future generations.
Differential survival and reproduction cause advantageous alleles to accumulate in the population over time.

Anahtar Kavram

Natural Selection and Differential Reproduction
Tahmini Süre:1m 0s
Soru 4846Soru →

Match each short-run cost concept on the left with its correct definition or property on the right.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Total Fixed Cost (TFC)
Marginal Cost (MC)
Average Variable Cost (AVC)
Average Fixed Cost (AFC)

Eşleşmeler

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Cevap

Total Fixed Cost (TFC) matches with 'Cost that remains constant regardless of the quantity of output produced'; Marginal Cost (MC) matches with 'The addition to total cost resulting from producing one extra unit of output'; Average Variable Cost (AVC) matches with 'Total variable cost divided by the total quantity of output produced'; Average Fixed Cost (AFC) matches with 'Total fixed cost divided by quantity, which continuously declines as output increases'.
Total Fixed Cost represents expenses that remain constant regardless of output. Marginal Cost measures the additional cost incurred when producing one extra unit. Average Variable Cost is total variable cost per unit of output. Average Fixed Cost is total fixed cost per unit of output, which declines continuously as output expands.

Adım Adım Çözüm

1
Identify the definition of Total Fixed Cost (TFC)
TFC is independent of output volume
By definition, fixed costs remain unchanged regardless of how much output is produced in the short run.
2
Identify the definition of Marginal Cost (MC)
MC is the addition to total cost from producing one more unit
Marginal refers to incremental change, calculated as MC=ΔTCΔQMC = \frac{\Delta TC}{\Delta Q}.
3
Identify the definition of Average Variable Cost (AVC)
AVC is variable cost per unit of output
Average variable cost is calculated by dividing total variable cost by total output (AVC=TVCQAVC = \frac{TVC}{Q}).
4
Identify the definition of Average Fixed Cost (AFC)
AFC is fixed cost per unit, which declines continuously as output rises
Since TFC is constant, dividing it by an increasing output QQ causes AFC to continuously diminish.

Anahtar Kavram

Definitions and properties of short-run cost concepts
Soru 4847Soru →

A manufacturing enterprise operating in a developing economy is determining whether to utilize fully automated assembly lines or hire additional manual laborers to manufacture agricultural tools. Which basic economic problem of society is this enterprise primarily addressing?

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Cevap: How to produce

Cevap

How to produce
The correct answer identifies the problem of 'How to produce', which deals with determining the specific combination of resources (labor vs. capital) and technological methods used in the production process.

Adım Adım Çözüm

1
Analyze the decision facing the enterprise in the scenario.
The firm is choosing between two production techniques: capital-intensive machinery versus labor-intensive manual work.
Identifying the nature of the economic choice is necessary to categorize the underlying fundamental economic problem.
2
Relate the input combination choice to the fundamental economic questions.
The choice of input proportions and technical methods of production corresponds directly to the problem of technique selection.
Economic theory defines 'How to produce' as the decision regarding which combination of factors of production (capital vs. labor) to employ.
3
Select the option representing factor combination.
The firm is resolving 'How to produce'.
This directly matches the technical decision highlighted in the scenario.

Anahtar Kavram

Basic Economic Problems of Society - How to produce
Tahmini Süre:1m 0s
Soru 4848Soru →

Match each digestive secretion or enzyme of the mammalian alimentary canal with its primary physiological function or mode of action in animal nutrition.

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Öğeler

Bile salts
Enterokinase (Enteropeptidase)
Ptyalin (Salivary amylase)
Rennin (Chymosin)

Eşleşmeler

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Cevap

Bile salts pair with lipid emulsification; Enterokinase pairs with trypsinogen activation; Ptyalin pairs with starch hydrolysis to maltose; Rennin pairs with caseinogen coagulation.
Each secretion or enzyme fulfills a distinct biochemical function: bile salts physically emulsify fats to assist lipase, enterokinase converts inactive trypsinogen into active trypsin in the small intestine, ptyalin hydrolyzes starch to maltose in the buccal cavity, and rennin precipitates milk protein in juvenile stomachs.

Adım Adım Çözüm

1
Identify the non-enzymatic role of liver secretions in fat digestion.
Bile salts reduce lipid surface tension without chemical cleavage, performing emulsification.
Increasing the lipid surface area enhances subsequent chemical digestion by lipase.
2
Determine the activation cascade of pancreatic proteolytic enzymes.
Enterokinase, secreted by the succus entericus, activates trypsinogen to trypsin.
Proteolytic enzymes are produced as inactive zymogens to prevent autolysis of gland tissues.
3
Analyze carbohydrate hydrolysis in the anterior alimentary canal.
Ptyalin (salivary amylase) breaks down cooked starch to maltose.
Amylase acts specifically on alpha-1,4 glycosidic bonds in cooked carbohydrates.
4
Examine specialized gastric protein digestion in young mammals.
Rennin converts soluble caseinogen to insoluble casein in the presence of calcium ions.
Precipitating milk protein slows gut transit time so pepsin can effectively digest it.

Anahtar Kavram

Digestive Secretions, Enzymes, and Functional Specificity
Soru 4849Soru →

A monopolist faces a market demand curve given by P=70−2QP = 70 - 2Q and operates with a short-run total cost function TC=50+10Q+Q2TC = 50 + 10Q + Q^2, where PP is the price in Naira (N\mathbb{N}) and QQ is the output level in units. What is the firm's profit-maximizing output level and its resulting short-run economic profit?

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Cevap: 1010 units of output and a profit of N250\mathbb{N}250

Cevap

The profit-maximizing output is 1010 units and the short-run economic profit is N250\mathbb{N}250.
To find the equilibrium output for a monopolist, set Marginal Revenue equal to Marginal Cost (MR=MCMR = MC). From the demand equation P=70−2QP = 70 - 2Q, Total Revenue is TR=70Q−2Q2TR = 70Q - 2Q^2, yielding MR=70−4QMR = 70 - 4Q. The derivative of Total Cost TC=50+10Q+Q2TC = 50 + 10Q + Q^2 gives MC=10+2QMC = 10 + 2Q. Equating 70−4Q=10+2Q70 - 4Q = 10 + 2Q yields 6Q=606Q = 60, so Q=10Q = 10 units. Substituting Q=10Q = 10 into the demand curve yields P=70−2(10)=N50P = 70 - 2(10) = \mathbb{N}50. Total Revenue is 10×50=N50010 \times 50 = \mathbb{N}500 and Total Cost is 50+10(10)+102=N25050 + 10(10) + 10^2 = \mathbb{N}250. Subtracting Total Cost from Total Revenue gives an economic profit of N250\mathbb{N}250.

Adım Adım Çözüm

1
Derive Total Revenue (TRTR) and Marginal Revenue (MRMR) functions from the demand curve.
TR=P×Q=(70−2Q)Q=70Q−2Q2TR = P \times Q = (70 - 2Q)Q = 70Q - 2Q^2, so MR=dTRdQ=70−4QMR = \frac{dTR}{dQ} = 70 - 4Q.
Monopoly pricing power implies MRMR declines at twice the rate of the linear demand curve.
2
Derive the Marginal Cost (MCMC) function from Total Cost (TCTC).
MC=dTCdQ=10+2QMC = \frac{dTC}{dQ} = 10 + 2Q.
Marginal cost is the first derivative of the total cost function with respect to output.
3
Equate MRMR and MCMC to find the profit-maximizing equilibrium output (QQ).
70−4Q=10+2Q  ⟹  60=6Q  ⟹  Q=1070 - 4Q = 10 + 2Q \implies 60 = 6Q \implies Q = 10 units.
All profit-maximizing firms produce where marginal revenue equals marginal cost.
4
Substitute equilibrium output into the demand function to find the selling price (PP).
P=70−2(10)=50P = 70 - 2(10) = 50 Naira.
The price a monopolist can charge is determined by consumer demand at the profit-maximizing output level.
5
Calculate Total Revenue (TRTR), Total Cost (TCTC), and Economic Profit (π\pi).
TR=50×10=500TR = 50 \times 10 = 500 Naira; TC=50+10(10)+(10)2=250TC = 50 + 10(10) + (10)^2 = 250 Naira; π=TR−TC=500−250=250\pi = TR - TC = 500 - 250 = 250 Naira.
Economic profit equals total revenue minus total cost.

Anahtar Kavram

Monopoly Short-Run Price and Output Determination
Tahmini Süre:2m 0s
Soru 4850Soru →

Match each type or characteristic of oligopoly on the left with its corresponding market description on the right.

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Öğeler

Collusive Oligopoly
Non-Collusive Oligopoly
Pure Oligopoly
Differentiated Oligopoly

Eşleşmeler

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Cevap

Collusive Oligopoly matches with firms agreeing on price and output to restrict competition; Non-Collusive Oligopoly matches with independent strategic behavior; Pure Oligopoly matches with producing identical/homogeneous goods; Differentiated Oligopoly matches with producing distinct, branded products.
Collusive oligopoly is defined by firm cooperation and collusion; Non-collusive oligopoly features independent strategic action; Pure oligopoly is characterized by homogeneous products; Differentiated oligopoly features distinct, branded products.

Adım Adım Çözüm

1
Analyze oligopoly categories based on market conduct and cooperation.
Collusive oligopolies feature cooperation and price agreement, while non-collusive oligopolies feature independent strategic rivalry.
Firm behavior regarding mutual agreements determines the collusive or non-collusive nature of the market.
2
Analyze oligopoly categories based on product differentiation.
Pure oligopolies involve homogeneous products like cement, while differentiated oligopolies feature distinct branded goods like motor vehicles.
Product nature distinguishes pure (standardized) from differentiated (heterogeneous) oligopoly structures.

Anahtar Kavram

Classification and types of oligopoly market structures
Soru 4851Soru →

In a non-collusive oligopolistic market for wireless telecommunication services, a major network provider operating at an equilibrium price of P0P_0 observes that raising its subscription rates leads to a sharp decline in total revenue, while lowering rates below P0P_0 yields negligible changes in sales volume. Based on the kinked demand curve model, which of the following explains this asymmetric revenue outcome?

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Cevap: Rival firms ignore price increases, making demand relatively elastic above P0P_0, but match price cuts, making demand relatively inelastic below P0P_0.

Cevap

Rival firms ignore price increases, making demand relatively elastic above the prevailing price, but match price cuts, making demand relatively inelastic below the prevailing price.
Under non-collusive oligopoly, Paul Sweezy's kinked demand curve model assumes asymmetrical rival behavior: competitors ignore price increases (making the demand curve elastic above the prevailing price P0P_0) and match price cuts (making the demand curve inelastic below P0P_0). This causes total revenue to fall when prices are raised and fail to increase when prices are lowered, reinforcing price rigidity at P0P_0.

Adım Adım Çözüm

1
Analyze the price increase scenario above the prevailing price P0P_0.
If the firm raises price above P0P_0, competitors do not follow because they can capture switching customers. Consequently, quantity demanded falls drastically, demonstrating that demand is relatively price elastic (Ed>1E_d > 1). Total revenue falls.
Competitors seek to gain market share at the expense of the price-raising firm.
2
Analyze the price cut scenario below the prevailing price P0P_0.
If the firm lowers price below P0P_0, competitors immediately match the price cut to prevent losing their customers. The initiating firm gains very little additional quantity, demonstrating that demand is relatively price inelastic (Ed<1E_d < 1). Total revenue does not rise significantly.
Competitors protect their existing customer base from price undercutting.
3
Combine the two behavioral responses to explain the asymmetric revenue outcome.
The asymmetry in rival behavior creates a 'kink' in the demand curve at price P0P_0, resulting in price rigidity, as any price movement away from P0P_0 decreases or fails to meaningfully improve total revenue.
Paul Sweezy's kinked demand model accounts for mutual interdependence under non-collusive oligopoly.

Anahtar Kavram

Price Interdependence and Sweezy's Kinked Demand Curve Model
Tahmini Süre:1m 30s
Soru 4852Soru →

An increase in the price of yam leads to a rise in the demand for cassava as consumers switch to an alternative staple food. What type of demand is demonstrated by cassava in this market scenario?

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Cevap: Competitive demand

Cevap

Competitive demand
Cassava and yam serve as alternative staple foods. When the price of yam increases, consumers substitute away from yam toward cassava, which demonstrates competitive demand.

Adım Adım Çözüm

1
Analyze the relationship between yam and cassava in the scenario
The two goods serve as alternative options to satisfy the same consumer want (staple food).
When the price of yam rises, consumers switch to purchasing cassava instead.
2
Identify the classification of demand for substitute goods
The demand for cassava is classified as competitive demand.
Competitive demand exists between commodities that are substitutes for one another.

Anahtar Kavram

Types of Demand (Competitive / Substitute Demand)
Tahmini Süre:45s
Soru 4853Soru →

Which of the following chemical changes occurs during the industrial conversion of a liquid vegetable oil into solid margarine via catalytic hydrogenation?

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Cevap: The degree of unsaturation decreases as carbon-carbon double bonds are converted to single bonds

Cevap

The degree of unsaturation decreases as carbon-carbon double bonds are converted to single bonds.
Vegetable oils are naturally liquid at room temperature due to their high degree of unsaturation (presence of multiple C=CC=C double bonds in the fatty acid tails). During industrial hydrogenation, hydrogen gas (H2H_2) is reacted with the oil using a nickel catalyst at elevated temperatures. This addition reaction converts unsaturated C=CC=C bonds into saturated C−CC-C single bonds, thereby decreasing the degree of unsaturation, increasing the packing efficiency of the molecules, and raising the melting point to produce solid margarine.

Adım Adım Çözüm

1
Identify the chemical structure of vegetable oils
Vegetable oils are liquid triacylglycerols (esters of glycerol and long-chain fatty acids) containing a high proportion of unsaturated carbon-carbon double bonds (C=CC=C).
Liquid fats have lower melting points due to kinks created by double bonds in the hydrocarbon chains.
2
Determine the reaction mechanism of catalytic hydrogenation
Addition of hydrogen gas (H2H_2) in the presence of a finely divided nickel catalyst converts C=CC=C double bonds into C−CC-C single bonds.
Adding hydrogen saturates the hydrocarbon chains, causing them to pack more tightly and raising their melting point to solidify the oil into margarine.

Anahtar Kavram

Hardening of Oils and Hydrogenation of Unsaturated Lipids
Tahmini Süre:1m 0s
Soru 4854Soru →

During a period of persistent demand-pull inflation, an economy experiences rapid increases in the general price level driven by excess aggregate demand. Which of the following fiscal policy measures should the government adopt to stabilize the economy?

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Cevap: Increase personal income tax rates and cut spending on public projects

Cevap

The government should implement contractionary fiscal policy by raising direct tax rates and cutting public spending to reduce aggregate demand and cool down inflation.
The correct action is to raise personal income taxes and reduce government spending. Higher tax rates lower disposable income for consumers, which decreases private consumption expenditure. Simultaneously, reduced government spending cuts public sector demand. Together, these contractionary fiscal measures lower aggregate demand and bring inflation under control.

Adım Adım Çözüm

1
Identify the macroeconomic problem
The economy is experiencing demand-pull inflation caused by excessive aggregate demand.
Economic stabilization requires dampening total expenditure to align demand with supply.
2
Distinguish fiscal policy instruments from monetary policy instruments
Fiscal policy involves government taxation and spending, whereas monetary policy involves central bank reserve ratios, interest rates, and open market operations.
The question specifically asks for a fiscal policy solution.
3
Select the appropriate fiscal direction
Contractionary fiscal policy (higher taxes and reduced public spending) contracts disposable income and aggregate demand.
Reducing total demand lowers pressure on overall price levels.

Anahtar Kavram

Contractionary Fiscal Policy for Inflation Control
Soru 4855Soru →

Consider the reversible gas-phase reaction represented by the equation below:

N2O4(g)⇌2NO2(g)ΔH=+57.2 kJ mol−1N_2O_4(g) \rightleftharpoons 2NO_2(g) \quad \Delta H = +57.2\text{ kJ mol}^{-1}

Which of the following conditions will shift the position of equilibrium to favor the yield of nitrogen dioxide (NO2NO_2)?

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Cevap: Increasing the temperature of the reaction vessel

Cevap

Increasing the temperature of the reaction vessel
Because the forward reaction absorbs heat (endothermic, ΔH>0\Delta H > 0), an increase in temperature shifts the position of dynamic equilibrium toward the right (forward direction) to absorb the excess thermal energy, thereby increasing the equilibrium yield of nitrogen dioxide (NO2NO_2).

Adım Adım Çözüm

1
Analyze the enthalpy change (ΔH\Delta H) of the forward reaction
The forward reaction N2O4(g)→2NO2(g)N_2O_4(g) \rightarrow 2NO_2(g) has ΔH=+57.2 kJ mol−1\Delta H = +57.2\text{ kJ mol}^{-1}, indicating an endothermic process.
Temperature perturbations affect equilibrium based on whether heat is absorbed or released.
2
Apply Le Chatelier's principle for a temperature increase
Increasing temperature adds heat energy to the system, causing the system to absorb heat by shifting in the endothermic (forward) direction.
The system opposes the stress of added heat by favoring the reaction direction that consumes heat.
3
Determine the effect on product yield
Shifting to the right increases the equilibrium concentration and yield of NO2(g)NO_2(g).
The forward reaction produces NO2(g)NO_2(g).

Anahtar Kavram

Le Chatelier's Principle and Temperature Perturbation
Soru 4856Soru →

A freshwater unicellular protist such as Amoeba continuously absorbs water from its hypotonic environment while producing metabolic nitrogenous waste. Which of the following correctly identifies the organelle responsible for maintaining osmotic balance and the primary mechanism by which its nitrogenous waste is eliminated?

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Cevap: Contractile vacuole for osmoregulation, and diffusion across the cell surface membrane for nitrogenous waste excretion

Cevap

The contractile vacuole functions in osmoregulation, while nitrogenous wastes are excreted via diffusion across the general cell surface membrane.
In freshwater protozoans like Amoeba, the contractile vacuole serves specifically for osmoregulation by collecting and pumping out excess water that constantly diffuses into the hypertonic cytoplasm. Nitrogenous waste, mainly ammonia, is small, soluble, and removed primarily by simple diffusion across the cell surface membrane into the aquatic environment.

Adım Adım Çözüm

1
Identify the osmoregulatory challenge of freshwater single-celled organisms
Because the interior cytoplasm of Amoeba is hypertonic to freshwater, water constantly enters the cell via osmosis.
To prevent bursting (osmotic lysis), excess water must be continuously gathered and discharged.
2
Determine the organelle responsible for water balance
The contractile vacuole collects excess intracellular fluid, migrates to the plasma membrane, and fuses with it to expel water externally.
This establishes the contractile vacuole as the dedicated osmoregulatory organelle.
3
Identify how metabolic waste products are discharged
Ammonia (NH3NH_3) is highly soluble and diffuses readily down its concentration gradient across the thin cell surface membrane.
Unicellular organisms lack specialized organ systems, relying on a high surface area-to-volume ratio for waste removal via simple diffusion.

Anahtar Kavram

Excretory mechanisms and osmoregulation in single-celled organisms
Tahmini Süre:1m 0s
Soru 4857Soru →

A monopolist faces a market demand function given by P=140−2QP = 140 - 2Q, where PP is the price in Naira and QQ is the output level. The total cost function of the firm is TC=20Q+Q2+200TC = 20Q + Q^2 + 200. What is the maximum economic profit, in Naira, earned by the monopolist at equilibrium?

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Cevap: 1000

Cevap

The maximum economic profit earned by the monopolist at profit-maximizing equilibrium is 1000 Naira.
To maximize economic profit, a monopolist sets marginal revenue equal to marginal cost (MR=MCMR = MC). From P=140−2QP = 140 - 2Q, TR=140Q−2Q2TR = 140Q - 2Q^2, giving MR=140−4QMR = 140 - 4Q. Differentiating TC=20Q+Q2+200TC = 20Q + Q^2 + 200 gives MC=20+2QMC = 20 + 2Q. Equating MR=MCMR = MC yields 140−4Q=20+2Q  ⟹  Q=20140 - 4Q = 20 + 2Q \implies Q = 20 units. Substituting Q=20Q = 20 into the demand equation gives price P=100P = 100 Naira. Total revenue is 20002000 Naira (100×20100 \times 20) and total cost is 10001000 Naira (20(20)+202+20020(20) + 20^2 + 200). The resulting maximum economic profit is 2000−1000=10002000 - 1000 = 1000 Naira.

Adım Adım Çözüm

1
Derive Total Revenue (TR) and Marginal Revenue (MR) functions
TR=140Q−2Q2TR = 140Q - 2Q^2 and MR=140−4QMR = 140 - 4Q
Marginal revenue is the first derivative of total revenue with respect to quantity.
2
Derive Marginal Cost (MC) function
MC=20+2QMC = 20 + 2Q
Marginal cost is the first derivative of total cost with respect to quantity.
3
Equate MR to MC to solve for the profit-maximizing output level (Q)
140−4Q=20+2Q  ⟹  6Q=120  ⟹  Q=20140 - 4Q = 20 + 2Q \implies 6Q = 120 \implies Q = 20 units
The necessary condition for profit maximization in all market structures is MR=MCMR = MC.
4
Determine the equilibrium price (P) from the demand curve
P=140−2(20)=100P = 140 - 2(20) = 100 Naira
Monopolists set price based on consumer willingness to pay at the profit-maximizing output level.
5
Calculate Total Revenue (TR), Total Cost (TC), and Economic Profit (\pi)
TR=100×20=2000TR = 100 \times 20 = 2000, TC=20(20)+(20)2+200=1000TC = 20(20) + (20)^2 + 200 = 1000, Profit =2000−1000=1000= 2000 - 1000 = 1000 Naira
Economic profit is the difference between total revenue and total cost at equilibrium output.

Anahtar Kavram

Monopoly Profit Maximization Condition (MR = MC)
Tahmini Süre:2m 30s
Soru 4858Soru →

Which system of taxation takes a higher percentage of income from higher-income earners than from lower-income earners?

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Cevap: Progressive tax system

Cevap

Progressive tax system
In a progressive tax system, the rate of tax increases as the taxable income increases. Consequently, individuals with higher incomes pay a larger percentage of their total income in tax compared to those with lower incomes.

Adım Adım Çözüm

1
Define the relationship between tax rate and income level.
Identify the system where the tax rate increases as income increases.
Tax systems are classified by how the tax rate changes relative to the taxpayer's income base.
2
Evaluate the definition against standard tax system types.
A system where high earners pay a higher proportion of income is defined as progressive taxation.
Progressive taxation is designed to reduce income inequality by scaling tax rates according to ability to pay.

Anahtar Kavram

Progressive Taxation
Soru 4859Soru →

Match each type of economic system listed on the left with its corresponding primary mechanism of resource allocation on the right.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Free Market Economy (Capitalism)
Command Economy (Socialism)
Mixed Economy
Traditional Economy

Eşleşmeler

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Cevap

Free Market Economy matches with resource allocation guided by consumer sovereignty, private ownership, and the price mechanism; Command Economy matches with resource allocation controlled entirely by a central planning authority and public ownership; Mixed Economy matches with resource allocation featuring the co-existence of private market forces and state intervention; Traditional Economy matches with resource allocation determined primarily by customs, habits, and ancestral traditions.
Each economic system is characterized by how it addresses the fundamental economic problems of what, how, and for whom to produce. Capitalist market systems rely on decentralized price signals, command economies use state planning directives, mixed economies integrate both market and government actions, and traditional economies depend on inherited social customs.

Adım Adım Çözüm

1
Identify the defining allocation mechanism for Free Market Economy.
Free market systems rely on private property and price signals resulting from market forces.
Consumer sovereignty and price mechanisms drive market decisions in capitalism.
2
Identify the defining allocation mechanism for Command Economy.
Command systems are centrally planned by state directives rather than price indicators.
Socialism places resource control under government authority.
3
Identify the defining allocation mechanism for Mixed Economy.
Mixed economies balance market operations with government regulatory and public service roles.
It combines aspects of both private enterprise and state intervention.
4
Identify the defining allocation mechanism for Traditional Economy.
Traditional economies answer production questions through historical custom and social roles.
Heritage and non-market customs govern economic activity in traditional systems.

Anahtar Kavram

Types of Economic Systems and their Resource Allocation Mechanisms
Soru 4860Soru →

In Paul Sweezy's kinked demand curve model for a non-collusive oligopoly, a firm observes that its price elasticity of demand is ∣Ed∣=2.5|E_d| = 2.5 for price increases above the prevailing market price P0P_0, but ∣Ed∣=0.4|E_d| = 0.4 for price cuts below P0P_0. Which of the following best explains the underlying behavioral assumption of rival firms and the resulting structure of the firm's marginal revenue curve?

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Cevap: Rival firms ignore price increases but match price cuts, creating a sharp change in demand elasticity at P0P_0 that results in a vertical discontinuity (gap) in the marginal revenue curve at the prevailing output level.

Cevap

Rival firms ignore price increases but match price cuts, creating a sharp change in demand elasticity at the prevailing price that results in a vertical discontinuity (gap) in the marginal revenue curve at the prevailing output level.
The correct option accurately captures the fundamental premise of Sweezy's kinked demand model: an oligopolist expects competitors to ignore price increases (making demand price-elastic above P0P_0) but match price reductions (making demand price-inelastic below P0P_0). This change in elasticity at P0P_0 creates a kink in the demand curve, which mathematically generates a discontinuous vertical gap in the marginal revenue curve at the existing output level.

Adım Adım Çözüm

1
Analyze rival firm reactions under non-collusive oligopoly according to Sweezy's hypothesis.
If a firm raises its price above P0P_0, rival firms will not follow, causing the price-raising firm to lose a significant market share (∣Ed∣=2.5>1|E_d| = 2.5 > 1, elastic segment). Conversely, if the firm lowers its price below P0P_0, rival firms immediately match the price cut to prevent losing customers, resulting in minimal extra market share gained by the firm (∣Ed∣=0.4<1|E_d| = 0.4 < 1, inelastic segment).
Establishing rival reaction patterns defines the shape of the firm's average revenue (demand) curve.
2
Examine the geometric relationship between the kinked demand curve and the marginal revenue (MR) curve.
Because the slope of the demand curve changes abruptly (kinks) at the prevailing output level corresponding to price P0P_0, the derived MR curve exhibits a vertical break or gap directly below the point of the kink.
Each linear or curved segment of demand produces its own MR line; the transition between the elastic upper portion and inelastic lower portion creates a vertical discontinuity.
3
Evaluate the economic implication of the vertical MR gap for price rigidity.
As long as the firm's marginal cost (MC) curve shifts within this vertical gap in the MR curve, the profit-maximizing condition MC=MRMC = MR continues to occur at the same output level and prevailing price P0P_0, explaining price stability (rigidity) in oligopolistic markets.
Synthesizes the behavioral assumptions with the structural characteristics of the kinked demand framework.

Anahtar Kavram

Kinked Demand Curve and Price Rigidity in Non-Collusive Oligopoly
Tahmini Süre:2m 0s
ÖncekiSayfa 243 / 697Sonraki
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