When v= 4.8 m/s:
E.K=mv²/2
=3,1(4.8)²/2
=35.712J
when v= 2(4.8):
E.K=mv²/2
=3.1(9.6)²/2
=142.848J
I assuming they are not going to be very big just small enough for the car to get over the top and not go backwards. The coasting is all the momentum thy have to get over the hill and they don't have a lot of momentum. hope this helps ☺
I think the correct answer from the choices listed above is the second option. The thermosphere has less air pressure than the mesosphere <span>because the farther away you are from the surface of the earth the lesser amount of gases present.</span>
The answer is D
Hope this helped