3. (30 points) There are three di erent production process for manufacturing the same type of shoes. Following is the cost structure in the manufacturing of two brands: Process Fixed Cost Per Year Variable Cost Per Unit A $95000 $3 B $90000 $4 C $88000 $4.5 (1) (7 points) Which brand is the most economical for a volume of 3800 units? (2) (7 points) Which brand is the most economical for a volume of 4200 units? (3) (16 points) How many units per year must be sold with each process to have annual pro tsof $20000 if the selling price is $7.5 per unit?