A spring is 17.0 cm long when it is lying on a table. One end is then attached to a hook and the other end is pulled by a force that increases to 25.0 N, causing the spring to stretch to a length of 19.2 cm.
1. How much work was needed to stretch the spring from 17.0 cm to 19.2 cm?
2. How long will the spring be if the 25.0 N forces is replaced with a 50.0 N force?