6. Assuming Cruise Company can purchase 6,000 units of the part from Suri Company for $21 each, and the facilities currently used to make the part could be rented out to another manufacturer for $24,000 a year, what should Cruise Company do?

a. Make the part and save $6.00 per unit.

b. Make the part and save $2.00 per unit.

c. Buy the part and save $2.00 per unit.

d. Buy the part and save $6.00 per unit.