Among 110 students in a probability class, on a three-question exam, 30 get question 1 incorrect, 40 get question 2 incorrect, and 23 get question 3 incorrect. Further, 20 students get both questions 1 and 2 incorrect, 15 get both questions 2 and 3 incorrect, and 8 get both questions 1 and 3 incorrect, and 7 get all three questions incorrect. Find the probability that a randomly selected student:
(a) Gets question 1 incorrect but gets question 2 correct.
(b) Gets questions 2 and 3 incorrect but gets question 1 correct.
(c) Gets all three questions correct.