Suppose Nancy has classes three days a week and attends classes three days 80% of the time, two days 15% of the time, one day 4% of the time, and no days 1% of the time. Let represent the number of days Nancy attends class in a week. What is the probability P(X=2)? Select one: a. 0.80 b. 0.04 c. 0.15 d. 0.01