Which one of the following statements is correct?

For lead storage battery,pick the correct statements:
$A.$ During charging of battery,$PbSO_4$ on anode is converted into $Pb$.
$B.$ During charging of battery,$PbSO_4$ on cathode is converted into $PbO_2$.
$C.$ Lead storage battery consists of a grid of lead packed with $PbO_2$ as cathode.
$D.$ Lead storage battery has $\sim 38\%$ solution of sulphuric acid as an electrolyte.
Choose the correct answer from the options given below:

For a saturated solution of $Ag_{2}CrO_{4}$ at infinite dilution,$\lambda_{m}^{\infty}(Ag^{+}) = 127 \ \Omega^{-1} \ cm^{2} \ mol^{-1}$ and $\lambda_{m}^{\infty}(CrO_{4}^{2-}) = 246 \ \Omega^{-1} \ cm^{2} \ mol^{-1}$. If the specific conductance of the solution is $2 \times 10^{-2} \ \Omega^{-1} \ cm^{-1}$,calculate the solubility product $(K_{sp})$ of $Ag_{2}CrO_{4}$.

$A$ battery is constructed of $Cr$ and $Na_2Cr_2O_7$. The unbalanced chemical equation when such a battery discharges is: $Na_2Cr_2O_7 + Cr + H^{+} \to Cr^{3+} + H_2O + Na^{+}$. If one Faraday of electricity is passed through the battery during charging,the number of moles of $Cr^{3+}$ removed from the solution is:

At $298 \ K$,the equilibrium constant is $2 \times 10^{15}$ for the reaction:
$Cu_{(s)} + 2 Ag^{+}_{(aq)} \rightleftharpoons Cu^{2+}_{(aq)} + 2 Ag_{(s)}$
The equilibrium constant for the reaction $\frac{1}{2} Cu^{2+}_{(aq)} + Ag_{(s)} \rightleftharpoons \frac{1}{2} Cu_{(s)} + Ag^{+}_{(aq)}$ is $x \times 10^{-8}$. The value of $x$ is (Nearest Integer).

Based on the following information,arrange four metals,$A$,$B$,$C$,and $D$,in order of increasing ability to act as reducing agents:
$(I)$ Only $C$ reacts with $1 \ M \ HCl$ to give $H_{2(g)}$.
$(II)$ When $A$ is added to a solution of the other metal salts,metallic $D$ is formed,but not $B$ or $C$.