ExplanationIf you substitute the given numbers into the expressions in Quantities A and B, you can compare them.
Substituting in Quantity A gives \((r - s)^4\) = \((2 - (-7))^4\) = \(9^4\).
Substituting in Quantity B gives \(r^4 - s^4\) = \(2^4 - (-7)^4\) = \(2^4 - 7^4\).
Without further calculation, you see that Quantity A is positive and Quantity B is negative.
Now consider the possibility that r = s. In that case both quantity A ans Quantity B are equal to 0. hence right option is option D.
Thus the correct answer is
Choice D.
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Sandy
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