An agency is having problems with personal phone calls made during working hours. Each minute of a personal call costs the agency $0.50 in wasted wages. The agency decides to hire operators to monitor calls in order to attain the optimal number of personal calls (minimize total cost of personal calls). Number of operators Total minutes of personal calls (per hour) 0 600 1 480 2 410 3 370 4 350 a.If operators receive $25 an hour, what is the minimum possible total cost of personal calls (per hour)? b. What is the most the agency would be willing to pay the first operator?