The following information for the past year is available from Gas Company, a company that uses machine hours to apply standard factory overhead cost to outputs: a Actual total factory overhead cost incurred Actual fixed overhead cost incurred Budgeted fixed overhead cost Actual machine hours Standard machine hours allowed for the units manufactured Denominator volume-machine hours Standard variable overhead rate per machine hour $ 28,000 $ 11,000 $ 10,000 5,380 5,050 5,750 $ 3 Under a three-variance breakdown (decomposition) of the total factory overhead variance, the factory overhead efficiency variance is