2. ME and RE are the mass and radius of the Earth, respectively. Neglecting the Earth's rotation, what is the energy needed to launch an object of mass m from the Earth surface into a circular orbital at altitude RE?
(A) 0
(B)
(C)
(D)
(E)
(A) 0
(B)

(C)

(D)
(E)

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統計: 尚無統計資料
統計: 尚無統計資料