The PlayaBowl stand in the mall sells custom acai bowls with various toppings. The stand owners want to provide superior service as they know there are many alternatives that customers can choose in the food court. As such, they want to determine the optimal staffing to meet customer demand. Customers arrive at the stand at an average rate of 20 customers per hour. Each server can typically serve an average of 11 customers per hour. The owners estimate that the cost of customer waiting is estimated at $25/hour per customer waiting and the cost of each counter server is $18 per hour, what is the optimal number of servers that should be working during the peak time? HINT: Use the Queueing.xls spreadsheet for calculations. You must show the cost analysis table for comparison.