Answer:
Process A: $1400
Explanation:
Giving the following information:
Process A: 1000 + 5*80= 1400
Process B: 500 + 15*80= 1700
Process C: 1500 + 3*80= 1740
The process with fewer costs in process A. We will recommend to use process A. If the production increases, there will be a point where the process C will be cheaper (because it has lower variable costs).