surelock manufacturing co. makes and sells several models of locks. the cost records for the zforce lock show that manufacturing costs total $23.00 per lock. an analysis of this amount indicates that $13.34 of the total cost has a variable cost behavior pattern, and the remainder is an allocation of fixed manufacturing overhead. the normal selling price of this model is $31.00 per lock. a chain store has offered to buy 10,000 zforce locks from surelock at a price of $16.10 each to sell in a market that would not compete with surelock's regular business. surelock has manufacturing capacity available and could make these locks without incurring additional fixed manufacturing overhead.