Can you explain step by step?

19 Ibar, Inc. uses a standard costing system in which it applies variable manufacturing overhead (VMOH) to products on the basis of machine hours (MHs). The company's standard requires 2 MHs for each unit produced with a standard rate of $40 per MH. During the last month, the company had the following activity: Budgeted number of units to be produced Actual number of units produced Actual VMOH cost VMOH Efficiency Variance 950 units 1,000 units $ 71,200 S 800 Favorable B. s The VMOH Rate Variance for the month was closest to: A. S 9,600 Favorable 8,000 Favorable C. $ 5,600 Favorable D. $ 4,000 Favorable E. None of the above