Which of the following is the weakest reducing agent?

Standard reduction potentials for the following reactions are :
$Fe^{3+} + 3e^{-} \rightarrow Fe ; E^{\circ}_{1} = -0.036 \ V$
$Fe^{2+} + 2e^{-} \rightarrow Fe ; E^{\circ}_{2} = -0.44 \ V$
What will be the standard electrode potential for
$Fe^{3+} + e^{-} \rightarrow Fe^{2+} (in $V$)?$

If standard reduction potentials $(E^0)$ of $(Al^{+3}_{(aq)}|Al(s))$, $(Fe^{+2}_{(aq)}|Fe(s))$, $(Cu^{+2}_{(aq)}|Cu(s))$ and $(Ag^{+1}_{(aq)}|Ag(s))$ are $-1.66 \text{ V}$, $-0.44 \text{ V}$, $+0.34 \text{ V}$ and $+0.79 \text{ V}$ respectively, which of the following reactions is non-spontaneous?

Given
$E^o_{\frac{1}{2}Cl_2/Cl^-} = 1.36 \ V$,$E^o_{Cr^{3+}/Cr} = -0.74 \ V$
$E^o_{Cr_2O_7^{2-}/Cr^{3+}} = 1.33 \ V$,$E^o_{MnO_4^-/Mn^{2+}} = 1.51 \ V$
The correct order of reducing power of the species $(Cr, Cr^{3+}, Mn^{2+}, Cl^-)$ will be:

If the emf of the cell $Cu(s) | Cu^{2+}(1M) || Ag^+(1M) | Ag(s)$ is $0.463 \text{ V}$ at $25^{\circ} \text{C}$ and the standard electrode potential of the $Cu$ electrode is $0.337 \text{ V}$, find the standard electrode potential of the $Ag$ electrode. (in $\text{ V}$)

Addition of powdered lead and iron to a solution which is $1.0 \, M$ in both $Pb^{2+}$ and $Fe^{2+}$ would result in [$E^{\circ}_{Fe^{2+}/Fe} = -0.44 \, V$ and $E^{\circ}_{Pb^{2+}/Pb} = -0.13 \, V$]