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Zorluk: OrtaDetermining Author's Primary Purpose

For centuries, architects and engineers have marveled at the resilience of ancient Roman concrete structures. While modern concrete structures often begin to degrade within a few decades, Roman monuments like the Pantheon and the Baths of Caracalla have survived for nearly two millennia, frequently in harsh maritime environments. To explain this disparity, researchers have historically pointed to the Roman use of volcanic ash, which reacts with water to form an exceptionally durable matrix. However, recent chemical analysis has revealed a more dynamic explanation. Scientists discovered that the concrete contains small, millimeter-sized white mineral blocks known as "lime clasts." Previously dismissed as evidence of sloppy mixing, these clasts actually act as a self-healing mechanism. When cracks form in the concrete, rainwater seeping into the fractures dissolves the calcium-rich clasts. This dissolved calcium recrystallizes within the cracks, sealing them and preventing further structural deterioration. By identifying this active chemical process, researchers have not only solved a historical puzzle but also suggested new pathways for developing self-healing concrete formulations in modern construction.

Which of the following best describes the primary purpose of the passage?

  1. A
    argue that ancient Roman builders possessed a superior understanding of chemistry and physics compared to modern engineers
  2. explain how recent scientific findings reveal the self-healing mechanism behind the durability of Roman concreteCevap
  3. C
    detail the historical role of volcanic ash in the initial development of Roman construction techniques
  4. D
    demonstrate that sloppy mixing techniques were the primary cause of structural cracking in ancient monuments

Cevap

explain how recent scientific findings reveal the self-healing mechanism behind the durability of Roman concrete
The correct answer correctly summarizes the primary objective of the passage. The author describes the long-lasting nature of Roman concrete, introduces the new discovery of lime clasts, details how these clasts chemically heal cracks, and discusses the implications for modern engineering. This makes the explanation of the self-healing mechanism the central purpose of the text.

Adım Adım Çözüm

1
Analyze the passage's structure and main topic.
The passage discusses Roman concrete's longevity, mentions volcanic ash as a prior explanation, and introduces a recent discovery—lime clasts that heal cracks.
Understanding the overall narrative arc helps separate the main focus from background details.
2
Evaluate the role of the recent discovery in the passage.
The discovery of lime clasts and their self-healing mechanism is presented as the primary solution to the mystery of Roman concrete's endurance.
Determining why the author introduced the new chemical analysis is key to finding the primary purpose.
3
Match the analysis to the options.
The option describing the explanation of recent scientific findings regarding the self-healing mechanism aligns perfectly with the main goal of the passage.
This confirms the correct option while eliminating choices that are too broad, focused on minor details, or factually inaccurate.

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Determining Author's Primary Purpose
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