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: If Mona is bouncing radar waves off a test car when training to be a policewoman and she notices the frequency of the waves returning to her radar gun is lower then it was before, what is happening to the car she is pointing the gun at? 
 Answer: decreasing in speed

Answer: A: As the car approaches the radar gun, the reflected microwaves get bunched up in front of the car. Therefore, the waves the receiver detects have a higher frequency than they would if they were being reflected from a stationary object. The faster the car is moving, the greater the increase in the frequency of the waves.


Question: Question: Shane sees two waterfalls; one made of hard stone, the other of soft rock. The waterfall with hard stone will have erosion that is, compared to the other, 
 Answer: lesser

Answer: The water erodes the softer rock faster than the harder rock.


Question: Question: If the Earth's orbit moves farther away from the Sun, what happens to the gravitational force between the two planets? 
 Answer: it decreases

Answer:
This is because the gravitational force of attraction between the Earth and Sun is stronger when the Earth is closer to the Sun.