Independent contractor - multiple states

[Csadler92]

This summer I worked as a student intern for NPS writing historical reports. My work contract was with Council of Maritime Museums who paid me and sent me an1099-NEC with their payer’s address in CT. The state income box was correct but the payer’s state no. box (box 6) was left blank.
 Most of my work was done remotely from FL and I was communicating and submitting my work to a federal office in Washington DC. For 12 weeks I had to travel to Michigan to conduct historical research for the reports which I composed when I returned to FL. 
What state(s) should I file an income tax return for? CT, MI, or DC? FL does not have state income tax.

[ErnieS0]

If you are a Florida resident, then you only have to file a nonresident state income tax return for Michigan.

You don't have to file for either Connecticut because you never worked in CT. Washington DC doesn't tax nonresidents and you never worked there anyway. You just submitted reports.

[Csadler92]

Thank you!! 
You helped answer a question that I have made SEVERAL calls about and no one could give me an answer. I appreciate your help! 

[Hal_Al]

You only pay MI income tax on the portion of your income, earned while physically working in MI.