Final answer:
A star that rises at 9:30 P.M. tonight will rise around 7:30 P.M. a month from now, due to the Earth's rotation and orbit around the Sun causing stars to rise approximately 4 minutes earlier each day.
Step-by-step explanation:
If a star rises at 9:30 P.M. tonight, approximately what time will it rise a month from now? The answer is 'c. None of the above'. Stars rise approximately 4 minutes earlier each day due to the Earth's orbit around the Sun. This time difference arises because a sidereal day, which is based on the Earth's rotation relative to the stars, is about 4 minutes shorter than a solar day, which is based on the Earth's rotation relative to the Sun.
Therefore, over the span of one month, the star's rise time would be adjusted by about 2 hours earlier (4 minutes x 30 days = 120 minutes). Since the star in question rises at 9:30 P.M. tonight, a month from now, it would rise around 7:30 P.M.