The spring is upstretched at the position x?= 0. Under the action of a force?P, the cart moves from the initial position?x1 = ?6 in. to the final position?x₂?= 3 in. Determine?

(a) the work done on the cart by the spring and?

(b) the work done on the cart by its weight.

Unstretched position 3 lb/in. K 15 1 Problem 3/97 14 lb -P