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: An increase in birth rates indicates a/an _____ in the food supply. 
 Answer: increase

A: Low food supply or a lack of space can lower birth rates, increase death rates, or lead to emigration.
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Q: Question: Dan falls from a single stair one day, then the next day falls down three stairs at once. After falling down one stair, compared to three, Dan will experience 
 Answer: less friction

A: Heavier objects press together with greater force, and this causes greater friction between them.
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Q: Question: If Milo is listening to the radio in his room and the room gets hotter, what happens to the speed of the sound waves generated by the radio? 
 Answer: increase

A:
For a given medium, sound waves travel more slowly at lower temperatures.
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