Sun Aviation Corporation is a global airline that flies to U.S., European and Asian destinations. Management informs you the US operation has incurred deductible expenses that are allocable to both its US and foreign operations:

Salaries of executives working at the New York office

Marketing expenses to maintain and enhance the global brand name

Interest expense

Fuel expenses

Airplane maintenance

State the methodologies or measurement factors you would apply to allocate each expense between US and foreign source income.

a. Salaries of executives working at the New York office

b. Marketing expenses to maintain and enhance the global brand name 

c. Interest expense 

d. Fuel expenses 

e. Airplane maintenance