An employee is up for their annual review. The employee believes that there is a 25% chance that they will receive a promotion. Furthermore, if the employee gets promotion there is an 85 % chance they will also receive a raise. However, if the employee does not get promotion there is still a 20% chance that they will receive a raise.

a) What is the probability that the employee will receive a raise?

b) If the employee does NOT receive a raise, what is the probability that the employee will not receive a promotion?