A college student frequents one of two coffee houses on campus, choosing Starbucks 70% of the time and Peet's 30% of the time. Regardless of where she goes, she buys a cafe mocha on 60% of her visits.
a. The next time she goes into a coffee house on campus, what is the probability that she goes to Starbucks and orders a cafe mocha?
b. Are the two events in part a independent?
c. If she goes into a coffee house and orders a cafe mocha, what is the probability that she is at Peet's?
d. What is the probability that she goes to Starbucks or orders a cafe mocha or both?