Assume that the net profit the doctor's office makes on a patient is $50. Recalibrating the three X-ray machines at a cost of $25,000 will ensure that the contrast index of all X-rays will fall within the tolerance limits. How long will the payback period be for this investment? Assume that the orthopedist's office is open eight hours a day, five days a week, and 50 weeks a year. This question is a continuation of part (d) above