A contractor is considering the purchase of an earth mover to avoid the cost of a rental unit. The earth mover costs $350,000 initially and will cost $7000 per year to store and maintain. When used, the operating cost is $300 per day to the contractor. A rental unit costs $500 per day to rent and operate. The contractor estimates that he would keep the earth mover 20 years and could then sell it at salvage for $20,000. He requires a 12% rate of return on any investment. Determine how many days per year he would have to operate the earth mover to make it a worthwhile purchase. Sketch the breakeven chart for this situation.