One hour, the hour hand passed 1, that is,
360/ 12=30 degrees, and the speed is 30 degrees per hour;
The minute hand went 1 lap, and the speed was 360 degrees per hour.
At 4 o'clock, it is the process that the minute hand catches up with the hour hand and then surpasses it.
At first, the angle between the minute hand and the hour hand is 90 degrees, and at 60 degrees, there are two situations:
1. Catch up with 30 degrees: 30/(360-30) =11hour =5 and 5/1/minutes, that is, 3: 05 and 5//.
2. Over 60 degrees after catching up:150/(360-30) = 5/1hour = 27 3/10/minute, that is, 3: 27 3//kloc-.