1) All text, so GIT will just see it, like any other file.
2) No, because of the above, he should add 16 mb to the repo (or less due to his own GIT compression), he will not add a new file every time, just change, so the repo will change to the size of the additions to the repository
3) No or GIT will not be able to see the differences - does GIT have its own compression anyway
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