Explain whether each of the following is an example of a macroeconomic concern or a microeconomic concern.

a. The Federal Aviation Administration (FAA) is considering increasing the number of takeoff and landing slots available at Ronald Reagan Washington National Airport.

b. In 2018, the U.S. federal corporate income tax rate was reduced from 35% to 21%.

c. In 2018, Maine raised its minimum wage from $9.00 per hour to $10.00 per hour.

d. Congress extends the maximum duration for the collection of unemployment benefits from 26 weeks to 52 weeks.