Supposea geyser has a mean time between eruptions of 68 minutes. Let the interval oftime between the eruptions be normally distributed with standard deviation 26minutes. (round everything to four decimal places)
a) What is the probability that a randomly selected time interval betweeneruptions is longer than 80 minutes? (round everything to four decimal places)
b) What is the probability that a random sample of 10 time intervals between eruptionshas a mean longer than 80 minutes? (round everything to four decimal places)
c) What is the probability that a random sample of 21 time intervals between eruptionshas a mean longer than 80 minutes? (round everything to four decimal places)