The following standard costs pertain to a component part manufactured by Bor Company: Direct materials........................ $ 4 Direct labor.............................. 10 Manufacturing overhead.......... 40 Standard cost per unit.............. $54 An outside supplier has offered to supply all of the parts needed by Bor Company for $50 each. The 60% of the manufacturing overhead cost that is fixed would be unaffected by this decision. In the decision "make or buy," what is the relevant unit cost to make the part internally?