Assume a Poisson random variable has a mean of 11 successes over a 121-minute period. a. Find the mean of the random variable, defined by the time between successes. b. What is the rate parameter of the appropriate exponential distribution? (Round your answer to 2 decimal places.) c. Find the probability that the time to success will be more than 63 minutes. (Round intermediate calculations to at least 4 decimal places and final answer to 4 decimal places.)