Boston Executive, Inc., produces executive limousines and currently manufactures the mini bar inset at these costs:

$\backslash$table$[[$Variable Costs:,$\backslash$table$[[$Variable Cost$],[$Amount:$]],$Fixed Costs:,$\backslash$table$[[$Fixed Cost$],[$Amount:$]]],[$Direct materials,$$950,$Depreciation $-$ equipment,$$500],[$Direct labor,$650,$Depreciation $-$ building,$200],[$Variable overhead,$300,$Supervisor salaries,$300],[$Total variable costs,$1,900,$Total Fixed costs,$1,000]]$

Assume that Boston Executive, Inc. uses the variable cost method of applying the cost$-$plus approach to product pricing and desires a profit equal to a $21\%$ return on invested assets of $$600,000.$

a$.$ Determine the variable costs and the variable cost amount per unit for the production and sale of $1,000$ mini$-$bars.

b$.$ Determine the variable cost markup percentage $($rounded to two places behind the decimal$)$ for mini$-$bars.

c$.$ Determine the selling price of mini$-$bars. $($Round markup to the nearest cent.$)$