Final answer:
Stars rise in the east 4 minutes earlier each night due to the difference between solar time and sidereal time. In two months, a star will rise about 4 hours earlier.
Step-by-step explanation:
Stars in the east rise 4 minutes earlier every night. This phenomenon occurs because the Earth rotates on its axis approximately once every 24 hours with respect to the Sun (solar time), but it actually takes about 23 hours and 56 minutes for the Earth to rotate once with respect to the distant stars (sidereal time). This difference means that each night, the stars will appear to rise and set 4 minutes earlier than they did the previous night. Therefore, in two months' time, or approximately 60 days, a star that rises at 8:30 p.m. one night will rise about 240 minutes earlier, which is equivalent to 4 hours earlier. This indicates that the star would rise at 4:30 p.m. two months later.