Answer:
- a. the changes that take place within an economic system as a whole.
- c. the challenges that economic systems face, such as inflation and unemployment.
- d. patterns of change within an economic system, as seen through economic models
Explanation:
Macroeconomics is concerned with the economy as a whole not just individual interactions between market participants. Problems such as inflation and unemployment affect the entire economy which is why it falls under macroeconomics.
With macroeconomics focusing on the economy as a whole, it shows the changes that an economy goes through over the years and this can usually be explained by economic models.
