Which of the following statements is CORRECT?

a$.$ If one of the assets to be used by a potential project is already owned by the firm, and if that asset could be sold or leased to another firm if the new project were not undertaken, then the net proceeds that could be obtained should be charged as a cost to the project under consideration.

b$.$ If one of the assets to be used by a potential project is already owned by the firm but is not being used, then any costs associated with that asset is a sunk cost and should be ignored.