4) Happy Pharmaceuticals produces three products using one machine. The machine has a total capacity of 200 machine hours. Product A sells for $13 per unit, has a variable cost per unit of $11, and each unit takes 1 machine hour to produce. Product As market demand is 150 units per week. Product B sells for $25 per unit, has a variable cost per unit of $15, and each unit takes 2 machine hours to produce. Product Bs market demand is 50 units per week. Product C sells for $3 per unit, has a variable cost per unit of $1, and each unit takes 0.8 machine hour to produce. Product Cs market demand is 200 units per week.

a) How many units of product C should the firm produce?

b) What is the maximum contribution margin the firm can achieve?

c) What is the maximum the firm should pay to increase its capacity by 200 machine hours?