An oven with a book value of $67,000 has an estimated 5 year life. A proposal is offered to sell the oven for $8,500 and replace it with a new oven costing $110,000. The new machine has a five year li S. fe with no residual value. The current oven has annual variable manufacturing costs of $73,000 per year. The new machine would cost $50,000 in annual variable manufacturing costs. What is the best opton-disposing or keping the old machine? By how much