Nonnegative real numbers $a$ and $b$ satisfy $\sqrt{a} - \sqrt{b} = 20.$  Find the maximum value of $a - 5b.$
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Nonnegative real numbers $a$ and $b$ satisfy $\sqrt{a} - \sqrt{b} = 20.$  Find the maximum value of $a - 5b.$
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Nonnegative real numbers $a$ and $b$ satisfy $\sqrt{a} - \sqrt{b} = 20.$  Find the maximum value of $a - 5b.$
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