It is known that 80% of students in an online statistics course watch all lecture videos prior to the midterm exam. Of those students who have watched all of the videos, 5% defer the midterm exam. Of those who have not watched all of the videos, 70% defer the midterm exam. Let V represent the event that a student watches all of the videos before the midterm exam, and let D be the event that a student defers the midterm exam.

• (a) [1.5]Express each of the three probabilities above in terms of the events V and D.
• (b) [3]If a student defers the midterm exam, what is the probability that they did not watch all lecture videos prior to the midterm exam? You must justify your answer using an appropriate formula.
• (c) [1]Are the events V and D independent? Explain using the appropriate probabilities.