Gelb Company currently makes a key part for its main product. Making this part incurs per unit variable costs of $$2\mathrm{.}00$ for direct

materials and $$1\mathrm{.}55$ for direct labor. Incremental overhead to make this part is $$1\mathrm{.}72$ per unit. The company can buy the part for $$5\mathrm{.}58$

per unit.