Okay, so having a bit of trouble with this problem. There is a spring loaded gun pointing vertically in the air. If the spring in the gun is compressed a distance of 0.147 m, the gun can launch a 25.4g projectile from rest to a maximum height of 24.0 m above the starting point of the projectile. Neglecting all resistive forces, determine the spring constant. What I've done so far is first assume the distance the projectile travels is irrelevant. Then using Hooke's law: k=mg/x so k=25.4(9.8)/0.147. I keep coming up with the answer 1693.3 N/m but am told that that is not correct. What am I doing wrong?