Macroeconomics 13th Edition by William Baumol ,Alan Blinder

Exercise 2

Which of the following problems are likely to be studied by a microeconomist and which by a macroeconomist
a. The rapid growth of Twitter
b. Why unemployment in the United States fell from 2010 to 2014
c. Why Japan's economy grew faster than the U.S. economy in the₁980s, but slower in the 2000s
d. Why the growth of health-care costs slowed down in recent years