A satellite of mass m completes one revolution around the earth at a constant speed s and radius r.
Which of the following statements are false?

a. The centripetal force is directed towards the center and is nonzero.
b. The net force is directed inwards towards the earth.
c. The satellite is accelerating.
d. The magnitude of the work done by the earth on the satellite is nonzero.
e. All of the above are true.