Two forces, of magnitudes F1=90.0 N and F2= 45.0 N , act in opposite directions on a block, which sits atop a frictionless surface, as shown in the figure. (Figure 1)Initially, the center of the block is at position xi= -2.00 cm . At some later time, the block has moved to the right, and its center is at a new position, xf= 5.00cm .

a-Find the work W1 done on the block by the force of magnitude F1= 90.0 N as the block moves from xi= -2.00cm to xf= 5.00cm .Express your answer numerically, in joules. b-Find the work W2 done by the force of magnitude F2= 45.0 N as the block moves from xi= -2.00cm to xf= 5.00 cm. Express your answer numerically, in joules.

c-What is the net work Wnet done on the block by the two forces? Express your answer numerically, in joules.

F- +X *=Xi