“Effective” dose is

Correct Answer: C

Rationale: The correct answer is C because the effective dose is a measurement that accounts for the different biological effects of various types of radiation on tissues or organs. It takes into consideration factors like the type of radiation, the energy, and the sensitivity of the exposed tissue. This makes it a more accurate representation of the potential harm caused by radiation exposure compared to simply measuring the amount of radiation present in the body (choice A) or accounting for shielding effects (choice B). Choice D is incorrect because the effective dose is not the same for gamma rays, beta particles, and alpha particles due to their different penetration abilities and biological impacts.

Correct Answer: D

Rationale: The correct answer is D, taking showers and baths. This is because, on average, showers and baths account for the largest portion of residential water use in the US. Watering lawns and washing clothes also consume significant amounts of water, but not as much as personal hygiene activities. Flushing toilets, while a daily necessity, uses less water compared to showers and baths. Therefore, D is the correct choice based on water usage statistics and typical household habits.

Correct Answer: D

Rationale: The correct answer is D: From oceans. The hydrological cycle starts with water evaporating from oceans due to solar energy. This evaporated water forms clouds, which eventually release precipitation back to earth. This continuous process of evaporation, condensation, and precipitation is known as the hydrological cycle. The other choices, A, B, and C, are incorrect because water primarily comes from oceans to initiate this cycle, not from reservoirs, glaciers, ice caps, lakes, or rivers.

Correct Answer: C

Rationale: The correct answer is C, Northern Africa and the Near East, because these regions are known to be experiencing severe water scarcity and water stress due to factors such as high population growth, limited water resources, and climate change impacts. Northern Africa and the Near East are characterized by arid and semi-arid climates, making them particularly vulnerable to water shortages. Additionally, rapid urbanization and unsustainable water management practices have exacerbated the situation in these regions. Choice A, Australia and Indonesia, is incorrect because while both countries face water challenges, they do not currently suffer from the same level of water scarcity as Northern Africa and the Near East. Choice B, North and South America, is also incorrect as water scarcity is not as severe in these regions compared to Northern Africa and the Near East. Choice D, Siberia and Northern Canada, is incorrect as these regions are known for their abundant freshwater resources and are not experiencing significant water scarcity issues.

Correct Answer: B

Rationale: The correct answer is B because prion diseases are caused by abnormal proteins called prions that can infect the brain. Eating the brain of an infected animal can introduce these prions into your body, leading to prion disease. Choice A is incorrect because prion diseases are not transmitted through touch alone. Choice C is incorrect because simply eating any brain does not guarantee infection with prions. Choice D is incorrect because prion diseases are not solely transmitted through cattle feed, but rather through direct consumption of infected brain tissue.