What is the primary goal or purpose of cellular respiration?

to provide energy to the living cell for carrying out metabolism

i'd say that the moon rock is about 2.2 billion years old.

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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