A satellite of mass m moves in an elliptical orbit around the Earth, as shown in the Figure. The minimum distance of the satellite from the Earth is called the perigee (indicated by p in the Figure) and the maximum distance is called the apogee (indicated by a in the Figure). If the speed of the satellite at p is vp, what is its speed va at a? (M denotes the mass of the Earth)
(A) va = vp
(B) va = vprp / ra
(C) va = Mvp / m
(D) va = mvp / M
(E) va = Gvp / rp