3. Consider a single-server queuing system. If the arrival rate is 90 units per hour, and each customer takes 38 seconds on average to be served, what is the average number of customers in the system. Should they add servers? Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer 19. no x Your answer b 12.9, yes 2.34, yes d 1.12, not enough info e 19, probably Answered - Incorrect. 2 attempts left Change your responses to resubmit Resubmit