l l Suppose a geyser has a mean time between eruptions of 97 minutes. Let the interval of time between the eruptions be normally distributed with standard deviation 29 minutes. Complete parts (a) through (9) below. (a) What is the probability that a randomly selected time interval between eruptions is longer than 111 minutes? The probability that a randomly selected time interval is longer than 111 minutes is approximately D. (Round to four decimal places as needed.) (b) What is the probability that a random sample of 7 time intervals between eruptions has a mean longer than 111 minutes? The probability that the mean of a random sample of 7 time intervals is more than 111 minutes is approximately (Round to four decimal places. as needed.) (c) What is the probability that a random sample of 21 time intervals between eruptions has a mean longer than 11 1 minutes? The probability that the mean of a random sample of 21 time intervals is more than 111 minutes is approximately D. (Round to four dkfcimal placesas needed.) 9