Which of the following is/are correct regarding the distinction between macroeconomics and microeconomics?

a) Salaries paid to Checkers employees is an example of a macroeconomic variable.

b) An import by Auto Spares of a new machine for painting cars is an example of a microeconomic variable.

a. appreciates against other currencies as well.

b. stimulates the exports and dampens the imports.

c. improves the balance of payments.