Q: Sand dunes migrate when sand is blown up a slope and this force pulls it down the other side? Choices: - earthquakes - air pressure - spin - gravity A:
gravity
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Q: Compared to free-floating bacteria, bacteria in biofilms often show increased resistance to what? Choices: - acid and detergents - alcohol and detergents - acid and antibiotics - antibiotics and detergents A:
antibiotics and detergents
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Q: The pain of angina means the heart muscle fibers need more what? Choices: - water - carbon - nitrogen - oxygen A:
oxygen
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Q: What is the term for electric current that keeps reversing direction? Choices: - direct current - AC/DC - magnetic current - alternating current A:
alternating current
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