Atlantic Manufacturing produces and sells children$$s bikes at an average price of $$120.$ Its costs are as follows: direct materials $=$ $$12$; direct labour $=$ $$8$; variable overhead $=$ $$4$; sales commission is $5\%$ of price. Its fixed monthly costs are $$47,000.$

Required:

$1.$ Using the above cost data, set up a monthly cost equation.

$2.$ What is the company$$s contribution margin percentage? $($Round your answer to $2$ decimal places.$)$