It's not so much the number of words that you put in but the structure and the content of your essays that matter. Of course, putting in a very well structured essay with great content but only 200 words will only mean that the essay is underdeveloped.
For AWA, try to flesh out your response in about 4-5 different paras, each containing a different point for your analysis. Within each para, try to support your reasoning with 4-5 sentences. At the end of it all about 15 words/sentence x 5 sentences x 5 paras = 375+ words. This should make for a well-rounded response.
If you are worried that you are not putting enough content to be meaningful, then make sure you are not addressing the issue from only one point of view.
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