Which statement best describes perigee?
a. the closet point in the moon's orbit to earth
b. the farthest point in the moon's orbit to earth
c. the closest point in earth's orbit of the sun
d. the sun's orbit that is closest to the moon

Complete these sentences. if a roller coaster train has a potential energy of 1,500 j and a kinetic energy of 500 j as it starts to travel downhill, its total energy isj. once the roller coaster train gets closer to the bottom of the hill, its kinetic energy increases to 1,100 j, and its potential energy decreases to j. when the train reaches the bottom of the track and is traveling along the ground, its kinetic energy isj.