Question: what are the requirements for filing taxes?
Answer: Single: $12,200 if under age 65. $13,850 if 65 and older.
Married filing jointly: $24,400 if both under 65. ... 
Married filing separately — $5 at any age.
Qualifying widow(er) with a dependent child: $24,400 if under 65. ... 
Head of household: $18,350 if under 65.