Answer.

Q2. An exponential distribution with a parameter can model the lengths of telephone calls 2 = 0.25 per minute, with the call lengths being independent. a. What is the probability that only two will be longer than one minute out of ten telephone calls? b. What is the probability that the length of a telephone call exceeds 45 seconds? C. What is the probability we receive more than two calls in 2 minutes? d. If we are concerned with telephone calls that exceed a half minute, what is the probability that the third one appears in the fifth trial