Archaeologists examining slag remnants from an early Iron Age smelting site hypothesized that local artisans added roasted acacia pods to laterite iron ore as a flux to reduce furnace smelting temperatures. Chemical analysis of the slag revealed unusually high concentrations of calcium oxide and phosphorus pentoxide, elements minimal in raw laterite ore. Because adding organic flux allows laterite ore to melt at significantly lower temperatures achievable by basic charcoal furnaces, the researchers concluded that the presence of these compounds proves the deliberate inclusion of acacia pods in the smelting mixture.
Which of the following statements, if true, strengthen the archaeologists' argument? Select all that apply.
- Subspecies of acacia trees native to the region yield seed pods whose ash contains calcium oxide and phosphorus pentoxide in proportions matching those detected in the smelting slag.Cevap
- Charcoal residues from fuel wood excavated alongside the furnace lacked the elevated calcium and phosphorus levels found in the slag.Cevap
- CSurrounding geological surveys identified nearby limestone deposits rich in calcium oxide that ancient metalworkers frequently utilized in ceramic kiln production.
- DArtifacts recovered from the site indicate that iron tools manufactured at lower furnace temperatures exhibited greater structural durability than tools forged at higher temperatures.
- EIron Age communities in adjacent regions possessed trade networks capable of supplying large quantities of acacia seed pods during peak smelting seasons.
Cevap
The argument is strengthened by the statements establishing that acacia pod ash matches the chemical proportions in the slag and that fuel wood charcoal was not the source of the calcium and phosphorus.
The conclusion asserts that acacia seed pods were deliberately added to laterite ore based on chemical evidence in the slag. To strengthen this claim, additional evidence must tie these specific chemical markers directly to acacia pods or rule out alternative origins. The statement matching the calcium and phosphorus ratios of native acacia ash directly to the slag confirms the chemical identity of the additive. Simultaneously, the statement verifying that furnace fuel wood charcoal lacked these elements eliminates timber fuel as a competing source of the compounds, thereby ruling out a key alternative explanation.
Adım Adım Çözüm
Anahtar Kavram
Strengthening causal claims by confirming unique chemical signatures and eliminating alternative potential causes.