For the spontaneity of a cell,which of the following is correct?

For the reaction $Cr_2O_7^{2-} + I^- \to I_2 + Cr^{3+}$,if $E_{cell}^o = 0.79 \ V$ and $E_{Cr_2O_7^{2-}}^o = 1.33 \ V$,then $E_{I_2}^o = $ ............. $V$.

Given the standard electrode potentials,$K^{+}/K = -2.93 \, V$,$Ag^{+}/Ag = 0.80 \, V$,$Hg^{2+}/Hg = 0.79 \, V$,$Mg^{2+}/Mg = -2.37 \, V$,and $Cr^{3+}/Cr = -0.74 \, V$,arrange these metals in their increasing order of reducing power.

The value of $x$ from the given data is

$2H^{+} \, (aq) + 2e^- \to H_2 \, (g)$. The standard electrode potential for the above reaction is (in volts):

For a cell constructed with $Cu$ and $Ag$ electrodes,which of the following statements is correct regarding the cathode and the standard cell potential $(E_{cell}^{\circ})$?