inner angle

The sum is four times the bottom angle, so the bottom angle is 45 degrees and the top angle is 90 degrees; If the base angle is twice the top angle, the sum of the internal angles of the whole triangle is five times the top angle, so the top angle is 36 degrees and the base angle is 0.

72 degrees

. The second question: Dad's age should be three times that of an integer, and the next eligible dad's age is 33. No, that's 36. This is the son's age 12, which is exactly three times. So five years later.