Solution: (1) If A does not explode, all possible numbers are: 5, 10, 15, 20, 25, 30, 35, so P (A does not explode).

(2) If B wins, all possible numbers are 10 and 15, so

P (B wins)

(3) A chooses not to turn for the second time.

B The second rotation must be selected, and only 25, 30 and 35 can be selected. At this moment,

P (B wins), so B is unlikely to win.

If A chooses for the second time, all possible numbers are: 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, so P (A) pops up.

More likely.

So a doesn't choose the second rotation.