X Company currently makes a part and is considering buying it next year from a company that has offered to supply it for $16.38 per unit. This year, total costs to produce 70,000 units were: Direct materials $420,000 Direct labor 378,000 Variable overhead 308,000 Fixed overhead 329,000 If X Company buys the part, $62,510 of the fixed overhead is avoidable. The resources that will become idle if they choose to buy the part can be used to increase production of another product, resulting in additional total contribution margin of $15,000. The marketing manager estimates that demand next year will increase to 74,150 units. If X Company buys the part instead of making it, it will save...