Ekapluto is an unknown planet that has two moons in circular orbits. The table summarizes the hypothetical data about the moons. (G = 6.67 × 10-11 N ? m2/kg2)
Mass Radius Orbital radius Orbital period
Moon A 4.0 × 1020 kg 2.0 × 108 m 4.0 × 106 s
Moon B 1.5 × 1020 kg 2.0 × 105 m 3.0 × 108 m
The mass of Ekapluto is closest to
A) 1.0 × 1022 kg.
B) 3.0 × 1022 kg.
C) 1.0 × 1023 kg.
D) 3.0 × 1023 kg.
E) 1.0 × 1024 kg.
Answer: D
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