If a binomial

is a factor of a polynomial, then

is a root of this polynomial.
It isn't easy really but you can always divide the number out. For example 50% of 200 is 100 by dividing 200 by 2 or 25% of 100 is 25 by dividing 100 by 4 since 25% is equivalent to 1/4
I do believe that the answer to your question is 60%
Surface Area of the Prism = (6x4) = 2(5x4) + 2(1/2x6x4)
Surface Area of the Prism = 24 + 40 + 24
Surface Area of the Prism =88 cm²
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Answer: Surface Area of the Prism =88 cm²
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The answer would be iii: 10-15%
the way to find this is to divide 43 by 381 to get 11.2% which falls in the rage of 10-15%