Senor Taco has had problems with its drive$-$through window operations. Customer cars arrive at an average rate of one every $30$ seconds with a standard deviation of $15$ seconds. Currently, Senor Taco can serve them in $25$ seconds, on average, with a standard deviation of $20$ seconds. They have designed their drive$-$through window operation to have only one window and once a customer car enters the line, they can$$t leave. They guarantee all customers will be served. Test results from a proposed process change didn$$t show any changes to service times, but the variability was reduced to $10$ seconds as measured by standard deviation. Then they put the process change into effect and were surprised to find that demand increased by $15\%.$

What impact will the proposed change have on the wait times of customers?

How much busier will the server at the window be with the process change? Can they still handle the increased load? Why?

Senor Taco is now concerned about physical space $$ how many more customers are in their drive$-$through window operations now?