If a firm can buy a machine for $60000, takes an investment tax credit of 15%, and lease out the machine for 9 years with lease payments at the beginning of the year, how much should the minimum annual lease payments be? Assume a 6-year straight-line depreciation, $9000 salvage and a tax rate of 21%. The after-tax required rate of return is 7.11%? $6,800 $6,900 $6,600 $6,100 $7,500