Which among the following equations represents the reduction taking place in a lead accumulator at the positive electrode,while it is being used as a source of electrical energy?

An aqueous solution of hydrazine $(N_2H_4)$ is electrochemically oxidized by $O_2$,thereby releasing chemical energy in the form of electrical energy. One of the products generated from the electrochemical reaction is $N_{2(g)}$.
Choose the correct statement$(s)$ about the above process:
$A$. $OH^{-}$ ions react with $N_2H_4$ at the anode to form $N_{2(g)}$ and water,releasing $4$ electrons to the anode.
$B$. At the cathode,$N_2H_4$ breaks to $N_{2(g)}$ and nascent hydrogen released at the electrode reacts with oxygen to form water.
$C$. At the cathode,molecular oxygen gets converted to $OH^{-}$.
$D$. Oxides of nitrogen are major by-products of the electrochemical process.

Identify the anode,cathode,positive electrode,and negative electrode for the $Daniell$ cell $(Zn-Cu)$ and the $Copper-Silver$ $(Cu-Ag)$ cell.

Observe the following statements about a dry cell:
$I$. It is a primary battery.
$II$. Zinc vessel acts as cathode.
$III$. $A$ paste of moist $NH_4Cl$,$MnO_2$ and $ZnCl_2$ is present between two electrodes.
$IV$. The potential of this cell is $1.5 \ V$.
The correct statements are:

Write reactions for the followings :
$1.$ Anode reaction of dry cell.
$2.$ Reduction reaction of dry cell.

What is the molar conductivity of $CH_3-CO_2H$ at infinite dilution?
Given that,
$\wedge_{m}^{o}(CH_3-CO_2)_2Ba = x_1 \ S \ cm^2 \ mol^{-1}$
$\wedge_{m}^{o}(BaCl_2) = x_2 \ S \ cm^2 \ mol^{-1}$
$\wedge_{m}^{o}(HCl) = x_3 \ S \ cm^2 \ mol^{-1}$