Replacement Machine $520,000 6 0 Old Machine Original cost $640,000 Useful life in years 12 Current age in years 6 Book value $400,000 Disposal value now $162,000 Disposal value in 6 years $0 Annual cash operating costs $107.000 For the decision to keep the old machine, the relevant costs of keeping the old machine is SO $61,000 O A $107.000 OB. $492,000 C. $642,000 OD. $804,000