The cost to produce Part A was $20 per unit in 2019. During 2020, it has increased to $25 per unit. In 2020, Sheridan Company has offered to supply Part A for $18 per unit. For the make-or-buy decision, O differential costs are $7 per unit. O incremental costs are $5 per unit. O incremental revenues are $7 per unit. net relevant costs are $5 per unit.