Please show answer and solution from a to d, queueing problem

Customers arrive at a bank according to a Poisson distribution with a mean of 45 customers per hour. Transactions per customer last about 5 minutes and are exponentially distributed. The bank wants to use a single-line multiple-teller operation, similar to the ones used in airports and post offices. The manager is conscious of the fact that customers may switch to other banks if they perceive that their wait in line is "excessive." For this reason, the manager want to limit the average waiting time in the queue to no more than 30 seconds. a) What is the value of arrival rate in customer per hour? b) What is the service rate in customers per hour? C) What type of queuing problem is this. Answer as single or multiple. d) What is the minimum number of servers that should be implemented