A customer who wants a coffee moves sequentially to 2 stations staffed by 4 employees in a Starbucks:

The customer first moves to one of the two cash registers where Alex and Bob are working. One of them places the order and accepts payment. There isone extra cash registerwhere no one is working.

One of Charlotte and David makes the coffee using a coffee machine. Both Charlotte and David have their own coffee machines. There isone extra coffee machinewhich is not used by anyone.

The task time of placing an order and accepting payment is 45 seconds. The task time of making a coffee is 60 seconds.

Tasks	Task time
Place a order & accept payment	45 seconds
Make a coffee	60 seconds

Note:Alex & Bob take the same amount of time to do their tasks.

Charlotte & David take the same amount of time to do their tasks.

(a) Draw the process flow diagram.

(b) What is the process capacity and what is (are) the bottleneck(s) of the process?

(c) What is the cycle time of the process?

(d) What is the flow time of the process?

(e) The Starbucks recruits a new staff Elena. It takes Elena 45 seconds to place an order & accept payment and 60 seconds to make a coffee. To improve the process capacity, which task should Elena be assigned to? What is the new process capacity?