<u><em>Answer:</em></u>
<u><em>Combustion</em></u>
<u><em>Explanation:</em></u>
<u><em>The step in the carbon cycle didn’t really exist before the industrial revolution was Combustion</em></u>
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<u><em>please mark me brainliest <3</em></u>
This is more of an answer based off of knowledge than fact, but i believe its that "New ideas often develop from unsuccessful experimentation."
I'm guessing it's the third one down
The smallest particle of an element is an atom