The Reno Company manufactures Part No$.498$ for use in its production line. The

manufacturing cost per unit for $20,000$ units of Part No$.498$ is as follows:

Direct materials $ $6$

Direct manufacturing labor $30$

Variable manufacturing overhead $12$

Fixed manufacturing overhead allocated $16$

Total manufacturing cost per unit $ $64$

The Tray Company has offered to sell $20,000$ units of Part No$.498$ to Reno for $$60$ per unit.

Reno will make the decision to buy the part from Tray if there is an overall savings of at least

$$25,000$ for Reno. If Reno accepts Tray$$s offer, $$9$ per unit of the fixed overhead allocated

would be eliminated. Furthermore, Reno has determined that the released facilities could be used

to save relevant costs in the manufacture of Part No$.575.$ For Reno to achieve an overall savings

of $$25,000,$ the amount of relevant costs that would have to be saved by using the released

facilities in the manufacture of Part No$.575$ would be which of the following: $($a$)$ $$80,000,($b$)$

$$85,000,($c$)$ $$125,000,$ or $($d$)$ $$140,000?$ Show your calculations.