\textbf{231-} If the ratio $\dfrac{K_{a_1}}{K_{a_2}}$ for the diprotic acid $\text{H}_2\text{A}$ equals $10^4$, the pH of a 0.05 molar solution is 0.05, and the solution is 0.01 molar, by how many units does the conjugate base differ approximately?
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\hspace{2cm} (1) $f$ \hspace{3cm} (2) $Y$ \hspace{3cm} (3) $Y$ \hspace{3cm} (4) $\varphi$
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