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.
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Question: Question: Dan notices that there were no new trees planted this year. Since there are so few trees in the area, Dan expects the air to be 
 Answer: dry

Answer: With fewer trees, the air is drier and droughts are more common.


Question: Question: Mona lives in a country with a lot of food available. If a natural disaster strikes and the food supply is cut off, what will happen to the birth rate in her country? 
 Answer: decrease

Answer: Low food supply or a lack of space can lower birth rates, increase death rates, or lead to emigration.


Question: Question: By pouring a pound of salt into a bucket of fresh water, could you cause the density of the water to 
 Answer: increase

Answer:
Water density increases as salinity and pressure increase, or as temperature decreases.