An analysis of maintenance cost at four levels of plant operations is shown below: Hours Cost Hours x cost Hours Squared 40 P 1,000 40,000 1,600 30 900 27,000 900 60 1,300 78,000 3,600 50 1,150 57,500 2,500 180 P 4.350 202.5 0 8.600 Under e least-squares ssions method, how much ise fixed st of the maintenance? th regre P 480 th co P 521 a. C