Which sound waves have a lower pitch?
- A. Those waves that are closer together
- B. Those waves that are farther apart
- C. Those waves that travel a long distance
- D. Those waves that travel a short distance
Correct Answer: B
Rationale: Sound waves that are farther apart have a lower pitch. The Doppler Effect explains that as objects emitting sound move away, the sound waves become more spaced out, resulting in a lower frequency and a lower pitch. Choice A is incorrect because waves that are closer together have a higher frequency and a higher pitch. Choices C and D are not directly related to determining the pitch of sound waves.
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What is the meaning of the word 'elasticity' in the last paragraph?
- A. Something that is able to resist and be flexible
- B. Something that is like plastic
- C. Something that is dynamic and electrifying
- D. Something that is silly
Correct Answer: A
Rationale: 'Elasticity' refers to the ability of the arterial walls to resist and be flexible, which affects blood pressure. In the provided extract, it is mentioned that an increase in blood pressure can occur if the arterial walls lose some of their elasticity with age or disease. This demonstrates that elasticity refers to the property of being able to resist and be flexible, supporting choice A as the correct answer. The other choices, B, C, and D, do not accurately reflect the concept of elasticity in the context of arterial walls and blood pressure.
What is the meaning of the word 'sterile' as it is used in the second paragraph?
- A. free of bacteria
- B. healthy
- C. delicious
- D. impotent
Correct Answer: A
Rationale: In the context provided, 'sterile' means free of bacteria. The text mentions that raw foods are not sterile and can be a common source of foodborne illnesses due to contamination with harmful bacteria. 'Healthy' (choice B) is incorrect as the term 'sterile' specifically refers to the absence of bacteria, not overall health. 'Delicious' (choice C) is irrelevant to the context of bacteria contamination. 'Impotent' (choice D) is also incorrect as it does not relate to the concept of being free from bacteria.
What is the meaning of the word 'ideal' as it is used in the first paragraph?
- A. thoughtful
- B. confined
- C. hostile
- D. perfect
Correct Answer: D
Rationale: In this context, 'ideal' means perfect. The human body provides a perfect environment for many microbes, as stated in the extract. It is the immune system's role to keep these microbes out or destroy them. The other choices are incorrect: 'thoughtful' does not fit the context of the sentence, 'confined' and 'hostile' are not synonymous with 'ideal' in this context.
What is the meaning of the word 'evolved' in the first paragraph?
- A. To spread
- B. To gradually develop
- C. To revolve
- D. To shift
Correct Answer: B
Rationale: In the context of the given extract, 'evolved' means to gradually develop. The systems in the body have evolved over time, indicating a gradual development and adaptation. 'To spread,' 'to revolve,' and 'to shift' do not capture the idea of a gradual development as portrayed in the text, making them incorrect choices.
What is the meaning of the word 'technical' as it is used in the fourth paragraph?
- A. requiring expert knowledge
- B. incomplete
- C. foreign
- D. plagiarized
Correct Answer: A
Rationale: The correct answer is 'A: requiring expert knowledge.' In the context provided, 'technical' refers to articles that demand expert knowledge to understand. The passage mentions that articles published in medical journals can be technical, meaning they are complex and require specialized expertise to comprehend. Choice B, 'incomplete,' is incorrect as 'technical' does not imply incompleteness. Choices C and D, 'foreign' and 'plagiarized,' are also incorrect as they do not align with the context of the passage.