1 pts The cost to produce Part A was $20 per unit in 2019. During 2020, it has increased to $23 per unit. In 2020, Supplier Company has offered to supply Part A for $18 per unit. For the make-or-buy decision, O net relevant costs are $3 per unit O incremental revenues are $5 per unit O differential costs are $5 per unit O incremental costs are $3 per unit