．For what value of $$\(A\)$$ will a circle of area $$\(A\)$$ quadruple its area by increasing the length of the circle＇$$\(s\)$$ radius by 1 ？ Note：$$\(A\)$$ can be written as $$\(k \pi\)$$ ，that is $$\(A=k \pi\)$$ ．Please enter the value of $$\(k\)$$ as your answer．

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