Based on the cost data, total cost is equal to: Output Total Variable Cost Total Cost 0 $0 $45 1 $40 S 2 $70 $115 3 $90 $_ Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a $40 when output is equal to 1 unit. b $45 when output is equal to 1 unit. C d $45 when output is equal to 3 units. $135 when output is equal to 3 units.