Julie drives 80 mi to grandmother's house. on the way to grandmother's, julie drives half the distance at 30 mph and half the distance at 50 mph . on her return trip, she drives half the time at 30 mph and half the time at 50 mph .how long does it take julie to complete the trip to grandmother's house?

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.