Ashopper in a supermarket pushes a cart with a force of 35ndirected at an angle of 25 degrees below the horizontal. the force is just sufficient to overcome various frictional forces, so the cart moves at a constant speed.

a. find the work done by the shopper as she moves down a 50.0mlength aisle.
b. what is the net work done on the cart? why?
c. the shopper goes down the next aisle, pushing horizontally and maintaining the same speed as before. if the work done by frictional force doesn't change, would the shopper's applied force be larger, smaller, or the same? what about the work done on the cart by the shopper?