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Hogle Mfg. Co. uses a standard costing system. The standard time to produce one unit is 4 hours, and normal production is 3,000 units monthly. Overhead costs were estimated to be $135,000. The standard variable overhead rate is $5 per machine hour. During April the following results were recorded: Units produced 3,100 Units sold 2,800 Machine hours required 12,800 Actual overhead costs $136,000 The combined fixed and variable overhead spending variance was: Select one: O A. $1,000 U O B. $2,000 F O C. $7,000 U O D. $3,000 F