In a Mercury cell,which of the following acts as a cathode?

Give the types and examples of electrodes.

The minimum voltage (in $V$) required to bring about the electrolysis of $1 \ M$ copper$(II)$ sulphate solution at $298 \ K$ is (Given $E^{\circ}_{Cu^{2+}/Cu} = 0.34 \ V$ and $E^{\circ}_{O_2/H_2O} = 1.23 \ V$)

Some statements about Leclanché cell are:
$(I)$ Anode is zinc metal
$(II)$ Cathode is graphite rod surrounded by powdered $MnO_2$ and carbon
$(III)$ Electrolyte is a moist paste of $ZnO$ and $KOH$
$(IV)$ Oxidation product is $ZnO$
The correct statements are:

The chemical reaction,$2AgCl_{(s)} + H_{2(g)} \to 2HCl_{(aq)} + 2Ag_{(s)}$ taking place in a galvanic cell is represented by the notation:

Copper displaces which of the following metals from their salt solutions?