Cathy is planning to take the Certified Public Accountant Examination (CPA exam). Records kept by the college of business from which she graduated indicate that 70% of students who graduated pass the CPA exam. Assume that the exam is changed each time it is given. Let n = 1, 2, 3, ... represent the number of times a person takes the CPA exam until the first pass. (Assume the trials are independent.)

(a) What is the probability that Cathy passes the CPA on the first try? (Use 2 decimal places.)

(b) What is the probability that Cathy passes the CPA exam on the second or third try? (Use 4 decimal places.)