Zookeeper Ltd has prepared the following cost estimates for the manufacture of a sub$-$assembly component, based on an annual production of $8,000$ units:A supplier has offered to make the sub$-$assembly at a price of $$16$ each. Two$-$thirds of fixed factory overheads, which represents executive salaries, rent, depreciation and taxes, continue regardless of the decision.RequiredShould the firm continue to make the subassembly?