.  The cost of
producing cell phones is represented as C=mx+b, where m is the marginal cost, x
is the number of phones produced, b
is the fixed cost, and C is the final cost. 


            a. If the
fixed cost is $75 and the marginal cost is $8, write the cost equation. 

            b. In
March, the total cost was $18,955. 
Calculate the number of phones   produced
using the equation.

            c. If the
goal for March was to produce at least 2000 phones, did the company      meet this goal?  Show mathematically the number of phones
exceeded or      missed the goal?