How would you categorize the following transactions in terms of aggregate expenditure?

a. A young musician buys a new electric bass guitar.

b. A bakery buys a new set of electric ovens to increase its production capacity by 50 percent.

c. A municipality buys construction material to fix potholes on the local roads.

d. The central government buys computers and office equipment for 15 economists working in the fiscal advisory council.

e. A group of four families buy large quantities of food at discounted prices.