PLEASE help its a question about rocks I'm tryna score a 80

The answer is C

Explanation:

lavas cool quickly at the earth's surface and are characterized by fine-grained texture, in which the crystals are too small to be seen by the unaided eye. Very quickly cooled lavas, typically those quenched in water, will have a glassy texture. They cool too quickly to form crystals.

1. dermis

2. chemical

3. urine

4. viruses

5. antibodies

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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