The predetermined overhead rate for Sheffield Corp. is $5, comprised of a variable overhead rate of $3 and a fixed rate of $2. The amount of budgeted overhead costs at normal capacity of $150000 was divided by normal capacity of 30000 direct labor hours, to arrive at the predetermined overhead rate of $5. Actual overhead for June was $8880 variable and $5200 fixed, and 1500 units were produced. The direct labor standard is 2 hours per unit produced. The total overhead variance is a)$920 F. b)$920 U. c)$1800 F. d)$1800 U.