Lee has been moving a crate that has a mass of 125 kg and required 120 j of work to move. the crate was moved a distance of 20 meters in 30 seconds. what was the power output?

Why does the equilibrium position of the spring change when a mass is added to the spring? will the mass oscillate around the new equilibrium position of the spring or the previous position without a mass attached to the spring? if the equilibrium position of the spring changes by 20 cm (assuming no initial mass) when a mass is added to the spring with constant 4.9 kg/s^2, what is the mass of the object attached to the spring?