A 10 kg object is on a movable platform. Rank the size of the normal force acting on the object from largest to smallest.
a) The object is at rest and the platform is not moving

b) the object is at rest on the stationary platform and there is a downward force of 10N applied to the top of the object while it remains stationary

c) the object is at rest on the stationary platform and there is an upward force of 10N applied to the top of the object while it remains stationary

d) the platform is accelerating the object upward at 1.5 m/s^2

e) the platform is accelerating the object downward at 0.5 m/s^2