The Terms "A

Multiple Choice

The terms "a.m." and "p.m." (as in see you at the movies at 8:30 p.m.) derive from what astronomical idea?

A) the Sun passes through the meridian in roughly the middle of the day
B) the Moon's phases change on a monthly cycle, getting fuller and then getting smaller
C) The apparent solar time differs from the mean solar time by a much greater amount in the first half of the day than the second half
D) The seasons in the northern hemisphere are backward from the seasons in the southern hemisphere
E) Putting the prime meridian in Greenwich, England required the approval of the prime minister. We think of time measurements as being either before or after that approval.
Section 4.4: The Calendar