A pharmacy currently works a two-line configuration to fill prescriptions and provide vaccinations. Each line has a dedicated cashier that collects payment and forwards the request to the team of pharmacists, who then call the customers. Every 10 minutes, on average, a customer arrives at the vaccination line. The cashier takesan average of 5 minutes to serve a customer, and there is, on average, 1 customer waiting in line. A customer looking for a prescription spends 12 minutes waiting and paying in the cashiers' area, which has 3 customers, on average, waiting and being served by the cashier. It takes the cashier in the prescription line 3 minutes to check out a customer.

What is the average total time a customer spends in the vaccination queue (waiting plus being served by the cashier)?

A.15 minutes.

B. 42 minutes.

C. 60 minutes.

D. 10 minutes.