The students studied two ponds. Class A studied a pond filled with protozoa, while class B studied a pond with almost no protozoa. Which class observed fewer protozoa predators keep many bacterial populations under control?
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Answer: class B

Two sister cities were part of an air pollution study. While Prague had big air pollution problems, Belfast was eco-friendly and its inhabitants were healthy. Which city had fewer people with an increased chance of dying from other diseases?
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Answer: Belfast

Samuel fills a glass cup with water and puts it in the freezer. He leaves the cup of water overnight and when he checks in the morning the cup has shattered. Confused he fills another cup with water and just leaves in on his kitchen counter. When he checks in the morning the glass is in tact. Will the amount of space water takes up increase or decrease when frozen?
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Answer:
increase