I am In the military. I am answering the question on supporting myself. Did I pay more than 1/2 my living expenses with earned income. I live in the baraks

Yes...you support yourself.  

The question is the more for people (usually unemployed) whose parents, or other family may be providing their support, housing, food, healthcare.

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It "might" be possible that you should say that you did not provide 1/2 your support ...IF...IF you joined the service late in 2016 and your parents provided your support up until then......but that's a stretch.  IF you might be in such a situation, you may need to talk to your parents to see how to handle that question for 2016....otherwise, you are now on your own......and working for the USA.