World Company expects to operate at 70% of its productive capacity of 38,000 units per month. At this planned level, the company expects to use 16,625 standard hours of direct labor. Overhead is allocated to products using a predetermined standard rate based on direct labor hours. At the 70% capacity level, the total budgeted cost includes $66,500 fixed overhead cost and $182,875 variable overhead cost. In the current month, the company incurred $421,625 actual overhead and 16,405 actual labor hours while producing 44,600 units. (Do not round intermediate calculations. Round "OH costs per DL hour" to 2 decimal places.)

a. Compute the predetermined standard overhead rate for total overhead.

b. Compute the total overhead variance.