You are the Chief Cost Accountant (CCA) for Super-Efficient Manufacturers WLL. Your Cost Accountant has given you the following variance information for the month of November 2020. Variance Calculation Formula Favorable (F) Unfavorable (U) Materials Price Variance MPV AQ(AP-SP) BD210 F Materials Quantity/Usage Variance MQV SP(AQ - SQ) BD500 U Labor Rate Variance LRV AH(AR-SR) BD250 F Labor Efficiency Variance LEV SR(AH-SH) BD100 U Variable Manufacturing Overhead Rate Variance VMRV AH(AR-SR) BD300 U SR(AH - SH) BD400 F Variable Manufacturing Overhead Efficiency Variance VMEV AQ Actual Quantity, AP Actual Price, SP Standard Price, SQ = Standard Quantity AH Actual Hours, AR = Actual Rate, SR Standard Rate, SH = Standard Hours Each of the above favourable (F) and Unfavorable (U) variances could be attributable to any number of possible causes. Most of these variances are the responsibility of either the Chief Purchasing Office (CPO) or the Chief Production Officer (CPO). Required: Write a professional letter (5 marks) to the Chief Executive Officer (CEO), covering the following. (a) For each of the six variances state and justify one possible cause. (9 marks) (b) For each of the six variances state, giving your reason, the most likely responsible Chief. (6 marks) (c) Define responsibility accounting and explain how standard costing can be used for responsibility accounting. (5 marks) (Total Marks 25 marks) (Note: professional letters include appropriate addresses, date, heading, and signature)