Block 2 (mass 1.30 kg) is at rest on a frictionless surface and touching the end of an unstretched spring of spring constant 259 N/m. The other end of the spring is fixed to a wall. Block 1 (mass 1.10 kg), traveling at speed v1 = 4.30 m/s, collides with block 2, and the two blocks stick together. When the blocks momentarily stop, by what distance is the spring compressed?