Difference between observation and inference

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An observation uses your five senses, while an inference is a conclusion we draw based on our observations. It might be helpful to have some examples. Observations can be made only with the five senses.

Explanation:

I'm not sure but hope it helps.

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.

condensation. good luck!