Bill and Susan Are Both Standing on Identical Skateboards (With

Bill and Susan are both standing on identical skateboards (with really good ball bearings) ,initially at rest.Bill weighs three times as much as Susan.Bill pushes horizontally on Susan's back,causing Susan to start moving away from Bill.Immediately after Bill stops pushing,

A) Susan and Bill are moving away from each other,and Susan's speed is three times that of Bill.
B) Susan is moving away from Bill,and Bill is stationary.
C) Susan and Bill are moving away from each other,with equal speeds.
D) Susan and Bill are moving away from each other,and Susan's speed is three times less than that of Bill.