Neve Commercial Bank is the only bank in the town of$$ York, Pennsylvania. On a typical$$ Friday, an average of $10$ customers per hour arrive at the bank to transact business. There is one teller at the$$ bank, and the average time required to transact business is $4$ minutes. It is assumed that service times may be described by the negative exponential distribution. A single line would be$$ used, and the customer at the front of the line would go to the first available bank teller. If a single teller is$$ used:

Part $2$

$$a$)$ The average time in the line$=$ enter your response here minutes$($round your response to two decimal$$ places$).$