I need help understanding how to do this problem. please show your work.

7.2 Scenario: The manager of a branch of a local bank wants to study the wait times for customers for teller services during the peak 12 noon to 1 pm lunch hour. A subgroup of three customers is selected (one at each 15-minute interval during the hour), and the time (wait time in minutes) is recorded. See the data shown to the right. Use this data to answer the questions that follow. 6. What is the Upper Control Limit for the Average Chart? Show your answer to two decimals 7. What is the Lower Control Limit for the Average Chart? Show your answer to two decimals. 8. What is the Upper Control Limit for the Range Chart? Show your answer to two decimals. 9. Plot the average and range charts below. 4.6 Wait Times (in minutes) Subgroup Cust. 1 Cust. 2 Cust. 3 1 8.4 7.9 2 5.6 8.7 7.3 3 5.5 7.3 3.2 4 8.0 5.4 5 9.7 4.8 6 8.3 8.9 9.1 7 4.7 6.6 5.3 8 8.8 5.5 8.4 9 5.7 4.7 4.1 10 1.7 4.0 3.0 11 2.6 3.9 5.2 12 4.6 2.7 6.3 Average Chart Range Chart Scenario: The manager of a branch of a local bank wants to study the wait times for customers for teller services during the peak 12 noon to 1 pm lunch hour. A subgroup of three customers is selected (one at each 15-minute interval during the hour), and the time (wait time in minutes) is recorded. See the data shown to the right. Use this data to answer the questions that follow. 6. What is the Upper Control Limit for the Average Chart? Show your answer to two decimals 7. What is the Lower Control Limit for the Average Chart? Show your answer to two decimals. 8. What is the Upper Control Limit for the Range Chart? Show your answer to two decimals. 9. Plot the average and range charts below. Wait Times (in minutes) Subgroup Cust. 1 Cust. 2 Cust. 3 7.2 8.4 7.9 2 5.6 87 7.3 3 55 7.3 3.2 4 44 8.0 5.4 5 9.7 46 4.8 6 8.3 8.9 9.1 7 4.7 6.6 5.3 8 8.8 5.5 8.4 9 5.7 4.7 4.1 10 1.7 4.0 3.0 11 2.6 3.9 5.2 12 4.6 2.7 6.3 Average Chart Range Chart Wait Times (in minutes) Subgroup Cust. 1 Cust. 2 Cust. 3 1 7.2 8.4 7.9 2 5.6 8.7 7.3 3 5.5 7.3 3.2 4 4.4 8.0 5.4 5 9.7 4.6 4.8 6 8.3 8.9 9.1 7 4.7 6.6 5.3 8 8.8 5.5 8.4 9 5.7 4.7 4.1 10 1.7 4.0 3.0 11 2.6 3.9 5.2 12 4.6 2.7 6.3