model?

$9.$ On average, how many customers are in the system in a single server model?

$10.$ On average, how many customers are in the line in a single server model?

$11.$ On average, how much time does a customer spend in the system in a single$-$server model? $($minutes$)$

$12.$ On average, how much time does a customer spend on hold in a single$-$server model? $($minutes$)$

As we leamed in the lecture, it is recommended you draw a picture of the underlined section of each question. Then draw a number line that will help you represent the entire statement. Hopefully, that will help you more easily get the correct answer.

$13.$ What is the probability there are exactly $1$ customer in line in a three$-$server model?

$14.$ What is the probability there are fewer than $3$ customers in line in a single server model?

$15.$ What is the probability there is more than one customer in the line in a twoserver model?

$16.$ What is the probability there is one or more customers in the line in a three$-$server model?

$17.$ What is the probability of being served immediately in a one$-$server model?

$18.$ What is the probability of being served immediately in a two$-$server model?

$19.$ What is the probability of being served immediately in a three$-$server model?

$20.$ How many employees are required to meet the account management department's goal of $90\%$ of incoming calls being served immediately?