Spacely's Sprockets produces widgets. At the beginning of the current year it estimated its overhead costs and normal capacity as follows; Annual Fixed Overhead, $90,000; Annual Variable Overhead, $210,000; and Machine Hours at 100% of Normal Capacity, 40,000 hours. During the month of October, Spacely's produced 2,000 widgets. The standard machine time is 1 hour per widget. Actual fixed overhead costs were $4,000 and actual variable overhead costs were $9,000. Compute the following variance: a.) variable overhead controllable variance b.) fixed overhead volume variance c.) total overhead variance