A 220 g block is dropped onto a relaxed vertical spring that has a spring constant of k = 2.8 N/cm (Fig. 7-30). The block becomes attached to the spring and compresses the spring 11 cm before momentarily stopping. (a) While the spring is being compressed, what work is done on the block by the gravitational force on it? (b) What work is done on the block by the spring force while the spring is being compressed? (c) What is the speed of the block just before it hits the spring? (Assume that friction is negligible.) (d) If the speed at impact is doubled, what is the maximum compression of the spring? I know that for the first part W=mg*delta y and the second part should be W=1/2Kx^2 but then i get a little lost on the last two questions. I know this is a spring force and gravitational question but does it also use kinetic? Every time i plug the numbers into the formula for kinetic energy it comes out wrong. Thanks!