Mikaelabelle Products sells product A at a selling price of $40 per unit. Mikaelabelle's cost per unit based on the full capacity of 500,000 units is as follows:

Direct materials $ 6

Direct labor 3

Indirect manufacturing (60% of which is fixed) 10

$19

A one-time-only special order offering to buy 50,000 units was received from an overseas distributor. The only other costs that would be incurred on this order would be $4 per unit for shipping. Mikaelabelle has sufficient existing capacity to manufacture the additional units. In negotiating a price for the special order, Mikaelabelle should consider that the minimum selling price per unit should be........... The answer is $17, but I want to know how do you get to that answer of $17. Thank you.