In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.

Q: Question: Marie is rolling cards down a hill. She wants to know which cart will get to the bottom of the hill slower, an empty cart, or a full cart? The cart that will finish first will have a mass that is 
 Answer: lower

A: An object has greater momentum if it has greater mass, greater velocity, or both.
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Q: Question: An increase in food will likely lead to _____ lifespans. 
 Answer: longer

A: New farm machines were invented. They increased the amount of food that could be produced. With more food, people were healthier and could live longer.
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Q: Question: Reid installed an aquifer 20m from the surface. Will installed an aquifer 10m from the surface. Whose aquifer is harder to get water from? 
 Answer: Reid

A:
The closer to the surface an aquifer is, the easier it is to get the water.
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