Lily (Self-Employed) Went from Her Office in Portland to Lisbon

Essay

Lily (self-employed) went from her office in Portland to Lisbon, Portugal, on business. While there, she spent part of the time on vacation. How much of the $5,000 airfare can she deduct based on the following assumptions:
a. Lily was gone five days (i.e., three business and two personal).
b. Lily was gone five weeks (i.e., four business and one personal).
c. Lily was gone five weeks (i.e., three business and two personal).