pls solve asap with proper formulas and steps. will surely upvote.

The Baytown Post Office has 4 stations for service. Customers line up in single file for service on an FIFO basis. The mean arrival rate is 55 per hour, Poisson distributed, and the mean service time per server is 4 minutes, exponentially distributed. Compute the operating characteristics for this operation. Does the operation appear to be satisfactory in terms of: (a) Postal workers' (servers') idle time; (Round answer to 3 decimal places, e.g. 2.750.) (b) customer waiting time and the number waiting for service; (Round customer waiting time to 2 decimal places, e.g. 2.75 and number of waiting for service to 3 decimal places. e.g. 1.276.) Wqmin Lq (c) the percentage of the time a customer can walk in and get served without waiting at all? (Round answer to 0 decimal places, e.g. 5\%.) P0 %