4. (25 points) Janice Weller, the manager of the customer service at the First Bank of Jefferson County, can hire employees with a high school diploma for $20,000 annually and employees with a bachelor's degree for $30,000. She wants to maximize the number of customers served, given a xed payroll. The following table shows how the total number of customers served varies with the number of employees. Total number of customers served Employee BA 5 HS dicloma (TB Hs) de- ree(TBBA) MBHSI Wane 1 120 100 2 220 190 3 300 270 4 370 330 5 380 6 Where: TBHs = total number of customers served by employees with HS diploma TBBA = total number of customers served by employees with BA degree Man = Additional or marginal number of customers served by employees with HS diploma MBBA = Additional or marginal number of customers served by employees with BA degree a. If Ms. Waller has a payroll of $160,000, how should she allocate this budget in order to maximize the number of customers served? b. What is the total number of customers served in part a? c. If her budget is increased to $240,000, how should she allocate this higher budget to maximize the number of customers served? d. What is the total number of customers served in part c