Question 3 (10 points) A small newspaper has three telephone lines. When none of the lines is busy, calls arrive randornlv, but at an average rate of about five per hour. However, when one line is busy (usually because a story is in progress), then new calls arrive at an average rate of about 20 per hour. When two lines are busy [usually because a breaking story is in progress), then new calls arrive at a rate of about 50 per hour. Of course, new calls cannot arrive when all three lines are busy. When there is just one call in progress (usually the initial report of a story}, it takes about 3 minutes to handle on average. When there are two or three calls in progress (usually updates to the ongoing story}, call duration is shorter, about 1.5 minutes on average. a. What is the probability that at least one of the telephone lines is free? In. What is the expected number of calls in progress? c. What is the expected amount of time that an individual caller will be on the telephone