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You don't need any reputation to write an answer, however, you do need reputation to add comments to posts. You can always post comments on your own posts or answers to one of your questions. Comments are meant for transient information such as improvement suggestions, clarification, or minuscule information. This also means that comments will be removed ...


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Unfortunately, the Stackexchange format doesn't lend itself to evolving a topic in one post. So, if your update to the question changes it so much that answers already given would become obsolete by being wrong, off-topic, or severely incomplete you should rather ask a new question instead. In this case, I think it could work out, but perhaps you should ...


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