Tax Question. Joe is 85 on social security $13,000 annually His wife Mary worked part time. They use to filed joint when they made $30,000 together years ago. Mary currently makes about $15,000 annually. Can she file single or must she file jointly. Is Joe's social security income taxable because it is mixed with Mary's taxable income

This is obviously a homework question, and we are specifically FORBIDDEN to answer homework questions.

Defeats the purpose of school.

Thank you so much.