A car driving at a constant speed of 78 mi/h travels 50 miles. How many hours did this take?

Can someone explain to me how to do this problem ?

If forces acting on an object are unbalanced, which factors may result fron an unbalanced force? check all that apply

Which of these is not a possible type of energy transformation? a. electrical energy into light energy b. sound energy into nuclear energy c. potential energy into kinetic energy d. kinetic energy into mechanical energy