A simple subject is whom or what the subject is about.
The answer is noun.
I think my answer would be @ first law of thermodynamics i hope that work i need the answer now lbvvs.
You didn’t post any question : step by step explanation
Extraneous means irrelevant or unneeded. essential means absolutely needed.
so they are opposites.
The other opposites in that set are mediocre (meh average) and extraordinary(amazing)
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