multiple channel queuing model

what option would I select using the following options:a. have one waiting line and have the first person in line go to the next available tellerb. have two waiting line: one teller for customer who have single transactions and four teller who wold handle customers who have multiple transactions.processing information: an average of 80 customers are processed on a noon hour. The average processing time for customers with single transaction is 90 seconds, while the processing time for customers with multiple transaction is 4 minutes. 60% of the customers are expected to have multiple transactions.