One of the major methods of problem solving used by economists is: a. intuition
b. custom
c. holistic approach
d. the marginal approach

In a simple answer, look at the study of economics, supply/demand, efficient pricing, lowering costs, etc. Now, take those into real world situations and APPLY the to solve the problems that every business has. The problem anyone dealing with economics, government, businesses, institutions have. Apply the economic theories, you will find that life in an office and the classroom can have different problems. Companies tend to be good at the very big stuff; raw materials, manufacturing, sales. Even there they can make improvements. But they spend a lot on transportation, communications, human resources. These things can be improved upon. Apply what you learned to real life problems and solve them.

the third answer is correct.

answertaxable income;