Pretty easy actually so because he says for every correct answer he gets he gets 4 points and he got 7 right to 4x7 = 28 so he has 28 right there then has 2 wrong answers so minus 2 from 28 you get 26 then minus another 2 cause he got 2 wrong and the = 24 then one point for unanswered so that would be 23.
Answer to question A = 23! Then you would have to get at least 7 questions right and 3 questions wrong. Hope this helps! ;D Answer to B = 7!
= 144