For the Seashell gas station in yourneighbourhood, records indicate that the number of customers arriving in any5-minute interval averages 0.94customers, with a standard deviation of 0.97 customers. Sixty-five (65) percent of the customers use a credit card to pay for their purchase. There are 8 pumps at this service station. The time that a car is parked at a pump is normally distributed with a mean of 6.35 minutes and a standard deviation of 2.10 minutes. All the above activities are independent of each other.

a) Ninety-four (94) percent of the customers will be parked for what maximum amount of time?

b) For 12 randomly selectedcustomers, what is the probability that at least 10 of them will pay using a creditcard?

c) What is the probability that more than 5 customers will arrive in a15-minute period?

d) What is the probability that the average parked time for the next 40 customers is less than 6minutes?