Patel and Sons Inc. uses a standard cost system to apply factory overhead costs to units produced. Practical capacity for the plant is defined as 55,800 machine hours per year, which represents 27,900 units of output. Annual budgeted fixed factory overhead costs are $279,000 and the budgeted variable factory overhead cost rate is $3.90 per unit. Factory overhead costs are applied on the basis of standard machine hours allowed for units produced. Budgeted and actual output for the year was 21,700 units, which took 44,800 machine hours. Actual fixed factory overhead costs for the year amounted to $267,000 while the actual variable overhead cost per unit was $3.80. Based on the information provided above, calculate the following factory overhead variances for the year. Indicate whether each variance is favorable (F) or unfavorable (U). (Do not round intermediate calculations. Round your final answers to nearest whole dollar amount.) a) Total overhead variance b) Total flexible-budget variance c) Production volume varinace