An Information Center open from 9:00 am to 5:00 pm is staffed by one employee. The length of service required by customers varies according to a normal distribution with a mean of 4.6 minutes and a standard deviation of 1.5 minutes. Customer arrivals are Poisson distributed with an arrival rate of 10 per hour. The manager wishes to find:

1) the average waiting time per tourist,

2) the percentage of time that the employee is busy (utilization),

3) the average number of tourists in the center,

4) the probability of finding two tourists in the center.

Must be in Excel and must show formulas.