This summer I lived in Washington DC and worked for a company based in Maryland. I worked in Virginia. How should I answer the question about making $ in other states?

[TomD8]

The answer to your question depends on whether or not you were a legal resident of DC.  Is your permanent residence in DC, or was your stay there temporary?  If temporary, did you live in DC for 183 days or more during the tax year?

DC and VA have tax reciprocity, but it applies only to legal residents of both jurisdictions.

DC would consider you an actual resident if you lived there 183 days or more during the tax year.

http://otr.cfo.dc.gov/node/383942