1.
Shane accidentally hit the alarm button
on his clock radio one evening before
he went out. The buzzer came on at
exactly 7:00p.m. Then it went off and
on at regular intervals. At 7:09 the
buzzer was off, at 7:17 it was on, and at
7:58 it was on. Was the buzzer on or off
at 9:00p.m.?