To convert masses to units of M_j, we need to divide the given mass by the mass of Jupiter:
1 M_j = 1.90 x 10^27 kg
(a) Mass of Saturn in M_j:
Mass of Saturn = 5.68 x 10^26 kg
Mass of Saturn in M_j = (5.68 x 10^26 kg) / (1.90 x 10^27 kg/M_j)
= 0.299 M_j
Therefore, the mass of Saturn in units of M_j is approximately 0.299 M_j.
(b) Mass of Earth in M_j:
Mass of Earth = 5.97 x 10^24 kg
Mass of Earth in M_j = (5.97 x 10^24 kg) / (1.90 x 10^27 kg/M_j)
= 0.00315 M_j
Therefore, the mass of Earth in units of M_j is approximately 0.00315 M_j.
(c) Mass of Neptune in M_j:
Mass of Neptune = 1.02 x 10^26 kg
Mass of Neptune in M_j = (1.02 x 10^26 kg) / (1.90 x 10^27 kg/M_j)
= 0.0537 M_j
Therefore, the mass of Neptune in units of M_j is approximately 0.0537 M_j.