Answer: Choice C) 9m^8
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Step-by-step explanation:
Each side of the square is the same, so we have length = width in this case.
Length = 3m^4
Width = 3m^4
Area = (length)*(width) = (3m^4)*(3m^4) = (3*3)*(m^4*m^4) = 9m^8
Note how m^4*m^4 leads to m^8. We add the exponents.
The general rule is a^b*a^c = a^(b+c).