30. The following costs were for Optimal View Inc., a contact lens manufacturer: Fixed Variable Total Output Costs Costs 300 $5,200 $12,000 350 5,200 400 5,200 450 Costs $17,200 14,000 19,200 16,000 21,200 5,200 18,000 23,200 At an output level of 425 lenses, per unit variable cost is calculated to be: A. $34.29. B. $48.00. C. $30.00. D. $35.56. E. $40.00. Unit variable cost = ($23,200 $17,200)/(450-300) = $402. The per unit cost variable cost of $40 is constant through the relevant range, including 425 units.