Given the Cost Function, C(x), and the Revenue Function, R(x)

Multiple Choice

Given the cost function, C(x) , and the revenue function, R(x) , find the number of units x that must be sold to break even.
-A store sells tents, sleeping bags, and camp stools. A customer buys a tent, 4 sleeping bags, and 3 camp stools for $220. The price of the tent is 7 times the cost of a camp stool. The cost of a sleeping bag is $20 more than the
Cost of a camp stool. Find the cost of each item.

A) $77 for a tent; $30 for a sleeping bag; $11 for a camp stool
B) $70 for a tent; $35 for a sleeping bag; $15 for a camp stool
C) $70 for a tent; $30 for a sleeping bag; $10 for a camp stool
D) $70 for a tent; $30 for a sleeping bag; $11 for a camp stool