Dart #1, shot from a spring-loaded toy dart gun, has a muzzle "velocity" of 12 m/s. Dart #2, identical to #1, is shot from the same gun, but this time the spring is compressed only half as far before firing. What is the muzzle "velocity" of dart #2? Neglect all friction and assume the spring to be ideal.

1. 3 m/s

2. 4 m/s

3. 6 m/s

4. 12 m/s

5. 24 m/s

6. 48 m/s

7. impossible to determine