4.58 Starbucks or Tim Hortons? A university student frequents one of two coffee houses on campus, choosing Tim Hortons 70% of the time and Starbucks 30% of the time. Regardless of where she goes, she buys a decaffeinated coffee 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 Tim Hortons and orders a decaffeinated coffee?

b. Are the two events in part a independent? Explain.

c. If she goes into a coffee house and orders a decaffeinated coffee, what is the probability that she is at Starbucks?

d. What is the probability that she goes to Tim Hortons or orders a decaffeinated coffee or both?