Nokea
Which sound waves have a higher 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: A
Rationale: Sound waves that are closer together have a higher pitch. This is explained by the Doppler Effect, where as a source of sound moves closer to an observer, the waves are compressed, resulting in a higher frequency and a higher pitch. Conversely, when the source moves away, the waves are stretched, leading to a lower frequency and a lower pitch. Therefore, choice A is correct. Choices B, C, and D are incorrect as they do not accurately describe the relationship between sound wave frequency and pitch.
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What is the meaning of the word 'pathogens' as it is used in the first paragraph?
- A. diseases
- B. vaccines
- C. disease-causing substances
- D. foods
Correct Answer: C
Rationale: In the context provided, 'pathogens' refers to disease-causing substances such as bacteria and viruses. These microorganisms can contaminate food and lead to foodborne illnesses. Choice A ('diseases') is incorrect as pathogens themselves cause diseases but are not diseases. Choice B ('vaccines') is incorrect as vaccines are used to prevent diseases caused by pathogens. Choice D ('foods') is incorrect as pathogens are not foods, but rather contaminants that can be found in food.
What is the meaning of the word 'deceptive' as it is used in the fifth paragraph?
- A. misleading
- B. malicious
- C. illegal
- D. irritating
Correct Answer: A
Rationale: In the context provided, 'deceptive' means misleading. The passage discusses how the Federal Trade Commission (FTC) regulates product advertising to ensure that all information is truthful and not misleading. Therefore, the correct answer is 'A: misleading.' Choice B, 'malicious,' is incorrect as it implies harmful intent, which is not necessarily conveyed by the term 'deceptive' in this context. Choice C, 'illegal,' is incorrect because 'deceptive' does not solely refer to something being against the law, but rather to misleading information. Choice D, 'irritating,' is also incorrect as it does not capture the essence of 'deceptive' as used in the passage.
What is the writer's primary purpose in writing this essay?
- A. To inform the reader about the dangers of high blood pressure
- B. To inform the reader how high blood pressure leads to a higher risk of heart attack
- C. To inform the reader how the cardiovascular system regulates blood pressure
- D. To persuade the reader that controlling one's blood pressure is important
Correct Answer: C
Rationale: The primary purpose of the essay is to inform the reader about how the cardiovascular system regulates blood pressure. The essay provides detailed explanations about the components of the cardiovascular system that regulate blood pressure, such as baroreceptors, chemoreceptors, and the kidneys. Choices A and B are incorrect because the essay does not focus on discussing the dangers of high blood pressure or its correlation with a higher risk of heart attack. Choice D is incorrect as the essay does not aim to persuade the reader to control their blood pressure but rather to educate them on the regulatory mechanisms of the cardiovascular system.
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 'enlist' as it is used in the second paragraph?
- A. call into service
- B. write down
- C. send away
- D. put across
Correct Answer: A
Rationale: In the context of the immune system, 'enlist' means to call into service. Immune cells recruit other cells to fight infection by producing chemicals that regulate their growth, behavior, and direct new recruits to trouble spots. This process is essential for the immune system's defense mechanism. The other choices are incorrect: 'write down' and 'put across' do not capture the action of mobilizing immune cells, and 'send away' is opposite in meaning to what is happening in the immune response.