instruction:
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.
question:
Question: If Mona is building a machine to help her vacuum her floor and she decreases the amount of force the engine inside the vacuum, what happens to the vacuum ability to make work easier? 
 Answer: decreases
answer:
Machines make work easier by increasing the amount of force that is applied, increasing the distance over which the force is applied, or changing the direction in which the force is applied.


question:
Question: Air pressure is higher in the 
 Answer: valleys.
answer:
Air pressure is less at higher elevations.


question:
Question: If the number of offspring of an species is increased, what happens to the number of traits they have in common with one another? 
 Answer: they will have more traits in common
answer:

Natural selection is the process by which living things with beneficial traits produce more offspring, so their traits become more common over time.