Explain differential costs, differential revenue, incremental cost, and avoidabl

Explain differential costs, differential revenue, incremental cost, and avoidable cost.  Give examples for each concept.
Explain opportunity costs and examine how opportunity costs are used in decision making.  Give examples of opportunity costs in decision making.
Examine the concept of the time value of money and how the concept is used in capital investment decision making.
Compare and contrast between net present value and internal rate of return methods.