For each of the following independent items, indicate whether the expenditure should be capitalized or expensed. Provide your reasoning.
a. A courier company changes the oil, oil filters, spark plugs, and air filters of the trucks in its delivery fleet.
b. An airline paints its aircraft with its new colours.
c. An office building replaces broken windows.
d. An office suite is rewired to allow for more phone lines to be installed so customer service can be improved.
e. The CPUs of 12 computers are replaced because of a defect.
f. The carpets in a law office are cleaned.
g. An extension is added to a building.
h. Staff is sent on a training program to develop their customer service skills.