A) $700

B) $515

C) $575

D) $125

RevampScamp purchased a Model A wheel grinder for $515 five years ago. Unfortunately, the wheel grinder stopped working. This wheel grinder could be replaced by a new Model B grinder costing $700 or a Model C grinder costing $575. RevampScamp decided to go with the Model C grinder. What is the total sunk cost regarding the decision to buy the Model C grinder rather than the Model B grinder