A 20.0 gram bullet is shot horizontally into a 2.00 kg block and quickly becomes imbedded in the block. After the impact, the block slides along a frictionless horizontal surface until it compresses a spring by 7.5 cm. The spring has spring constant k = 3200 N/m.
(a) What is the initial speed of the bullet?
(b) How much energy is dissipated in the block during the impact?