Question 4 In a school sports day, each student is required to join at least one event. The following table represents the probability distribution function of the number of events (X) a student takes part in the sports day. X 2 4 5 P(X = X) 0.25 0.375 1.5k k 0.05 (a) What is the value of k? (2 marks) (b) Find E(X) and o (X). (4 marks) (c) Suppose the number of events students take part are independent. In a group of 6 students, what is the probability that exactly 4 students join at least 2 events? (4 marks) (total: 10 marks)