The following standards for variable manufacturing overhead have been established for a company that makes only one product: Standard hours per unit of output .............. 5.2 hours Standard variable overhead rate................. $14.10 per hour The following data pertain to operations for the last month: 6.400 hours Actual hours.. ........ Actual total variable overhead cost............ Actual output ...... .. $88,320 units 1,200 units Reference: 10-19 What is the variable overhead spending variance for the month? O $336 F O $336 U O $1,920 F $1,920 U