100 divided by 20 equals 5, that is to say, the five-point answer to a question is 19, and the six-point answer to a question is 19, which equals 95, but he got 94 points, that is to say, a wrong question was deducted, that is, a wrong question was deducted.

(1) Solution: Suppose he got the X question right and got the (20-x) question wrong.

20x-(20-x)=76

20x-20+x=76

Hee hee, I can't solve the equation. I haven't learned it. sorry

② Impossible.