Answer:
Macroeconomics deals with events that affects the entire country or industry as a whole while Microeconomics affects individual members of the economy such as companies and people.
A. Congress recently passed the Tax Cuts and Jobs Act of 2017. MACRO
This Act will affect the entire nation so it will fall under Macroeconomics.
B. Amazon now has a 40% share of all e-commerce revenues. MICRO
Amazon is a single company in the market so things related to it will be considered on a micro economic level.
C. Tuition at the local university increased 11% from last year. MICRO
The local university like Amazon, is a single body in the economy and so they are a microeconomic player.
D. The U.S. unemployment rate fell below 4% in 2018. MACRO
The unemployment rate of a nation relates to the nation as a whole so this will fall under macroeconomics.
