A 2.0 kg block slides along a horizontal surface with a coefficient of friction µk = 0.30. The block has a speed of v = 1.3 m/s when it strikes a massless spring head-on (a) If the spring has a force constant k = 120 N/m, how far is the spring compressed? (b) What minimum value of the coefficient of static friction, µs, will assure that the spring remain compressed at the maximum compressed position? (c) If µs is less than this, what is the speed of the block when it detaches from the decompressing spring? [Hint: Detachment occurs when the spring reaches its natural length (x = 0).] Explain why detachment occurs when the spring reaches its natural length. I'm able to do a) but not the others. thanks for your help.