Two heavenly bodies S_1 and S_2not far off from each other are seen to

1.	Two heavenly bodies S_1 and S_2not far off from each other are seen to revolve in orbit
Answer» around their common centre of mass which are orbitrary with `S_1`FIXED and `S_2`MOVING ROUNDS `S_1` with `S_2`fixed and `S_1`moving round `S_2` ANSWER :A

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