68% of all students at a college still need to take another math class. If 49 students are randomly selected, find the probability that a. Exactly 32 of them need to take another math class. b. At most 31 of them need to take another math class. c. At least 35 of them need to take another math class. d. Between 31 and 39 (including 31 and 39) of them need to take another math class.