Rent a wreck car rental agency has a contract with PM warranty, Inc. to do major repairs for $700 per car. The car rental agency estimates that it could repair its own cars for $300 each if it acquires a facility for $300000 now. A salvage value of $400000 after 15 years is estimated for the facility. What is the minimum number of cars that must be repaired each year to make the acquisition attractive at an interest rate of 10% per year?