For a given medium, sound waves travel more slowly at lower temperatures.  Compared to sound waves travelling through a cup of ice water, would sound waves travelling through a cup of boiling water move slower or faster??
faster?
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The higher up a food chain that humans eat, the greater the levels of toxic metals they take in.  A human who eats an animal that is low on the food chain should take in more or less toxic metals?
less
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The greater the mass of the objects, the stronger the gravitational pull between them.  Two planets with very small masses will have a stronger or weaker gravitational pull between them than two planets with small masses?
weaker
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Objects with greater mass have a stronger force of gravity between them.  A planet that is smaller has less gravity or more gravity?
less gravity
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