the following data have been provided by mathews corporation: budgeted production 6,900 units standard machine-hours per unit 9.4 machine-hours standard lubricants rate $1.20 per machine-hour standard supplies rate $1.00 per machine-hour actual production 7,000 units actual machine-hours (total) 66,230 machine-hours actual lubricants cost (total) $78,100 actual supplies cost (total) $66,536 lubricants and supplies are both elements of variable manufacturing overhead. the variable overhead rate variance for supplies is closest to: $736 u $736 f $306 u $430 u