Urgent !!! Center of mass and relevant stuffs 1. The problem statement, all variables and given/known data A vertical spring of constant k is attached at the bottom to a platform of mass mp, and at the top to a massless cup. The platform rests on a scale. A ball of mass mb is placed in the cup. What is the reading on the sacle when (a) the spring is compressed an amount d= mb*g/k (b) the ball comes to rest momentarily with the spring compressed ? (c) the ball again comes to rest in its original position ?? 2. Relevant equations F=Ma 3. The attempt at a solution I have no clue how to solve this one. can someone help me ??