ECO 201 Unit 4 Homework Assignment. Assignment Direction At the end of each chapter is a section titled "Key Concepts", and next to each concept is a corresponding page where you will find its definition. Please expand on the text's given definition, using other relevant terms from the chapter, and also give a practical example of that key concept. Please don't simply supply the text definition. This is not what I want. I'm looking for your input showing a basic understanding of each "Key Concept". A 1 or 2 sentence answer is not acceptable, nor is a few bullet points. Show me you understand the concept. This is due for each chapter.