A solid block of mass m2 = 2.4 kg, at rest on a horizontal frictionless surface, is connected to a relaxed spring (with spring constant k = 240 N/m) whose other end is fixed. Another solid block of mass m1 = 2.4 kg and speed v1 = 4.0 m/s collides with the 2.4 kg block. If the blocks stick together, what is their speed immediately after the collision? What is the maximum compression of the spring?