A spring and block are in the arrangement of Fig. When the block is pulled out to x = + 4.0cm, we must apply a force of magnitude 360 N to hold it there. We pull the block to x = 11 cm and then release it. How much work does the spring do on the block as the block moves from xi = +5.0 cm to
(a) x = + 3.0 cm
(b) x = - 3.0 cm,
(c) x = - 5.0 cm, and
(d) x = - 9.0 cm?