QUESTION $3$

Car arrivals at a bank's drive$-$through follow a Poisson distribution with a rate of $16$ cars per hour. The teller can serve up to $20$ cars per hour and the servic exponential distribution. What is the utilization factor of the teller?

a$.60\%$

b$.65\%$

c$.70\%$

d$.75\%$

e$.80\%$