Thunder lightning manufacturing, inc. developed its annual manufacturing overhead budget for its master budget for 2021 as follows: expected annual operating capacity 120,000 direct labor hours variable overhead costs indirect labor$600,000 indirect materials120,000 factory supplies 60,000 total variable 780,000 fixed overhead costs depreciation240,000 supervision120,000 property taxes 96,000 total fixed 456,000 total costs$1,236,000 the relevant range for monthly activity is expected to be between 8,000 and 12,000 direct labor hours. prepare a flexible budget for a monthly activity level of 8,000 and 9,000 direct labor hours.