Hi, again and thank you for waiting.
I found an article regarding the man who slipped and fell into the Norris Hot Springs in Yellowstone, approximately 3 years ago. The answer to your question is that the body completely dissolved and that's what would happen to the guy you have in the picture, too. This happened because The parks' geyers and springs are acidic (as you asked earlier) because they are fed by thermal water, deep underground, that picks up sulfuric acid as it rises to the surface. The sulfuric acid is produced by microorganisms that break down hydrogen sulfide in rocks and soil.
Here is the article, if you would like to read it:
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So, because the hot springs and geysers are acidic, combined with the very high temperatures they contain, a human who accidentally fell in one of them would dissolve--everything would dissolve.
I hope this helped you further and I cannot answer any more questions for you in this thread, as we're only allowed to answer one question per request. I'm sure you understand. : )