When $E^o_{Ag^{+}/Ag} = 0.8 \ V$ and $E^o_{Zn^{2+}/Zn} = -0.76 \ V$,which of the following is correct?

For the reduction of $NO_3^{-}$ ion in an aqueous solution,$E^0$ is $+0.96 \ V$. Values of $E^0$ for some metal ions are given below:
$V^{2+}_{(aq)} + 2e^{-} \rightarrow V \ \ \ \ E^0 = -1.19 \ V$
$Fe^{3+}_{(aq)} + 3e^{-} \rightarrow Fe \ \ \ \ E^0 = -0.04 \ V$
$Au^{3+}_{(aq)} + 3e^{-} \rightarrow Au \ \ \ \ E^0 = +1.40 \ V$
$Hg^{2+}_{(aq)} + 2e^{-} \rightarrow Hg \ \ \ \ E^0 = +0.86 \ V$
The pair$(s)$ of metals that is(are) oxidized by $NO_3^{-}$ in aqueous solution is(are):
$(A) V$ and $Hg$
$(B) Hg$ and $Fe$
$(C) Fe$ and $Au$
$(D) Fe$ and $V$

The standard reduction electrode potentials of four metals are $A = -0.250 \ V$,$B = -0.140 \ V$,$C = -0.126 \ V$,and $D = -0.402 \ V$. Which metal can displace $A$ from its aqueous salt solution?

Using the standard electrode potentials given below,identify the correct statements from the following.
$Fe^{2+} + 2e^{-} \longrightarrow Fe ; E^{\circ} = -0.44 \ V$
$Cu^{2+} + 2e^{-} \longrightarrow Cu ; E^{\circ} = +0.34 \ V$
$Ag^{+} + e^{-} \longrightarrow Ag ; E^{\circ} = +0.80 \ V$
$(i)$ Copper can displace iron from $FeSO_4$ solution.
$(ii)$ Iron can displace copper from $CuSO_4$ solution.
$(iii)$ Silver can displace copper from $CuSO_4$ solution.
$(iv)$ Iron can displace silver from $AgNO_3$ solution.

The standard reduction potential at $298 \ K$ for the following half cells are given below :-
$NO_3^{-} + 4H^{+} + 3e^{-} \rightarrow NO_{(g)} + 2H_2O \quad E^0 = 0.97 \ V$

$V^{2+}_{(aq)} + 2e^{-} \rightarrow V_{(s)}$	$E^0 = -1.19 \ V$
$Fe^{3+}_{(aq)} + 3e^{-} \rightarrow Fe_{(s)}$	$E^0 = -0.04 \ V$
$Ag^{+}_{(aq)} + e^{-} \rightarrow Ag_{(s)}$	$E^0 = 0.80 \ V$
$Au^{3+}_{(aq)} + 3e^{-} \rightarrow Au_{(s)}$	$E^0 = 1.40 \ V$

The number of metal$(s)$ which will be oxidized by $NO_3^{-}$ in aqueous solution is $....$.

Given that the standard potentials $(E^{\circ})$ of $Cu^{2+}/Cu$ and $Cu^{+}/Cu$ are $0.34 \ V$ and $0.522 \ V$ respectively,the $E^{\circ}$ of $Cu^{2+}/Cu^{+}$ is (in $V$)