Green Corporatoin has budgeted 2.5 of direct labor hours per gizmo, at a standard cost of $22 per hour, for producing 220 gizmos. During April, technicians actually worked 555 hours, producing 232 gizmos, which were all sold. Green Corporation paid the technicians $24 per hour. The standard cost for variable overhead is $13 per direct labor hour. What is Green's direct labor efficiency variance for April? A. $550 F OB. $660 U O C. $110 U OD. $600 F