the management of a company manufacturing surfboards has fixed costs (zero output) of $ 200 per day and total costs of $3 800 per day at a daily...

the management of a company manufacturing surfboards has fixed costs (zero output) of $ 200 per day and total costs of $3 800 per day at a daily output of 20 boards. 

a. Assuming the total costs per day C is linearly related to the total output per day (X), write an equation relating these two quantities. 

b. What are the total costs for an output of 12 boards per day?

c. Graph the equation for 0<X<20.