Answer:
The Axes. The independent variable belongs on the x-axis the(horizontal line) of the graph and the dependent variable belongs on the y-axis the (vertical line)
When the base and the height of a triangle are the same. the hypotenuse is that number times sqrt2.
B and C are 7, so a would also be 7
Given , revenue function : 
Cost function 
Profit = Revenue - Cost
Hence, P = R(x) - C(x)
Total revenue for x = 12000 is 
Total cost for x = 12000, 
Profit = 60000-28500 = 31500
Answer = 31500