Jax company assembles products from a group of interconnected parts. Some of these parts are produced in the company and some are purchased from outside vendors. The vendor for part X has just increased the price by 35 percent, to $10 per unit for the first 5,000 units and $9 per additional units ordered each year. The company used 7,500 units of Part X each year. Unit cost if Jax company make the part are: Direct material $3.50 Direct labour $1.75 Variable manufacturing overhead $4.25 Variable selling cost for assembled product $3.75 Required: Should the company continue to purchase the part, or should it begin making the part inhouse?