Students at a University take a Probability exam in three classrooms. The number of students who are well-prepared (W) and poorly-prepared (P) for the exam in each of the three classrooms are as follows:

Classroom I: 60 W, 20 P;

Classroom II: 50 W, 30 P;

Classroom III: 65 W, 15 P.

Students who are well prepared pass the exam with a probability of 0.85, while students who are poorly prepared pass the exam with a probability of 0.5.

(i) We select a classroom randomly and then from this room we select a student at random. What is the probability that he/she passes the exam?

(ii) If the student selected has passed the exam, what is the probability that he/she took the exam in classroom II?