Oliver Industries is evaluating the manufacturing process for one of their products. Oliver has determined that the process has yearly maintenance costs of $$29,000,$ yearly operating costs of $$22,000,$ and yearly revenues of $$97,000.$ Two years ago, the firm spent $$6,000$ upgrading the equipment used to make this product, and it expects to spend $$5,000$ on additional upgrades three years from now. In this scenario, Oliver

does not have any sunk costs.

has sunk costs of $$6,000.$

has sunk costs of $$5,000.$

has sunk costs of $$51,000.$