Bank management printers, inc., produces luxury checkbooks with three checks and stubs per page. each checkbook is designed for an individual customer and is ordered through the customer’s bank. the company’s operating budget for september 2017 included these data: number of checkbooks 15,000 selling price per book $ 20 variable cost per book $ 8 fixed costs for the month $145,000 the actual results for september 2017 were as follows: number of checkbooks produced and sold 12,000 average selling price per book $ 21 variable cost per book $ 7 fixed costs for the month $150,000 the executive vice president of the company observed that the operating income for september was much lower than anticipated, despite a higher-than-budgeted selling price and a lower-than-budgeted variable cost per unit. as the company’s management accountant, you have been asked to provide explanations for the disappointing september results. bank management develops its flexible budget on the basis of budgeted per-output-unit revenue and per-output-unit variable costs without detailed analysis of budgeted inputs. required prepare a static-budget-based variance analysis of the september performance. prepare a flexible-budget-based variance analysis of the september performance.