7. The gravitational potential energy of a body depends on its A speed and position B. mass and volume. C. weight and position D. speed and mass​

Aboxcar traveling at 12 m/s approaches a string of 5 identical boxcars sitting stationary on the track. the moving boxcar collides and links with the stationary cars and they all move off together along the track. what is the final speed of the cars immediately after the collision? (you may take the mass of each boxcar to be 18,537 kg.)

Find v(t), given acceleration a(t)=7j and initial velocity v(0)=k

Most of the volume of an atom is occupied by the