Which of the following acts constitute investment according to the economist’s definition of that term?
a. Pfizer builds a new factory in the United States to manufacture pharmaceuticals.
b. You buy 100 shares of Pfizer stock.
c. A small drug maker goes bankrupt, and Pfizer purchases its factory and equipment.
d. Your family buys a newly constructed home from a developer.
e. Your family buys an older home from another family.