Xia Co. currently buys a component part for $7 per unit. Xia believes that making the part would require $4.20 per unit of direct materials and $1.20 per unit of direct labor. Xia allocates overhead using a predetermined overhead rate of 235% of direct labor cost. Xia estimates an incremental overhead rate of $0.60 per unit to make the part. 1-a. What are the relevant costs for Xia to make or buy the part? (Round your answers to 2 decimal places.) Per Unit Make Buy 1-b. Should Xia make or buy the part? O Make ?? Buy