You push a 15 kg box of books 2.0 m up a 25 incline into the back of a moving van. The box moves at a constant velocity if you push it with a force of 95 N. (Assume your push is parallel to the incline and the coefficient of friction is 0.248.) Find

1. the work done by normal force on the box
2. the work done by your push on the box
3. the work done by gravity on the box
4. the work done by friction when friction is equal to 18N