Answer:
1. B
2. B
3. D
4. A
Hope this was correct! A lot of the answers are already in the article itself and the wording is just different. I suggest now that for information retainment, you read the article again with the correct points in mind and see if you can spot the points where the answers are stated!
Acceleration = velocity / time.
Answer:
The frequency of sound heard by the boy is 1181 Hz.
Explanation:
Given that,
Frequency of sound from alarm 
Speed = -8.25 m/s
Negative sign show the boy riding away from the car
Speed of sound = 343
We need to calculate the heard frequency
Using formula of frequency

Where,
= frequency of source
= speed of observer
= speed of source
= speed of sound
Put the value into the formula

here, source is at rest


Hence, The frequency of sound heard by the boy is 1181 Hz.
The answer is a. Hope this helps :)
Answer:
the faster an object moves the more kinetic it has. the more mass an object has, the more kinetic energy it has.