Given a scientific question, generate a correct answer to it.
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Question: Orbiting at a fairly typical 370 kilometers, the international space station is an example of what?

Answer: manmade satellite

Question: Carboxylic acids have an acidic hydrogen atom, but esters do not. what do esters have in place of an acidic hydrogen atom?

Answer: hydrocarbon group

Question: Vaccinations are designed to boost immunity to a virus to prevent this?

Answer:
infection