b. For a randomly selected office hour, the number of students who will go is 2.2.

с. For a randomly selected office hour, the number of students expected to go will vary from the mean by 2.2 students.

d. For a random selection of office hours, the average number of students expected to go is 2.2.

e. For a random selection of office hours, the E average number of students expected to go will vary from the mean by 2.2 students.