Stopping production of a particular production

Company A is considering when to of a particular product in its product line. to manufacture the product is specialized but can readily be sold as . If the decision rule for this case says keep producing the product as long as the contribution to net earnings is positive, what if anything is wrong with that? Contribution to where t= the tax rate, (1-t) ( to manufacture product. Suggested solution guide Think about that some income from tax, this shield must be taken into account in the contribution equation