A 10.8 kg weather rocket generates a thrust of 250.0 N. The rocket, pointing upward, is clamped to the top of a vertical spring. The bottom of the spring, whose spring constant is 407.0 N/m, is anchored to the ground. Initially, before the engine is ignited, the rocket sits at rest on top of the spring. After the engine is ignited, what is the rocket's speed when the spring has stretched 15.8 cm past its natural length? What would be the rockets speed after travelling the distance if it weren't tied down to the spring?