Howelll audio manufactures military compact discs. the standard hours 27 minutes; standard rate per hour $6.40; standard cost $2.88. 9,145 hours of direct labor hours to make 19,100 discs, the direct labor cost total is $56,699. the budgeted overhead rate is $4.10 per direct labor the company incurred $42,067 in variable manufacturing overhead cost what is the variable overhead efficiency variance and variable overhead rate variance.