Which of the following equations represents the cell potential?

The $E^{\ominus}$ for $Cl_{2}/Cl^{-}$ is $+1.36 \ V,$ for $I_{2}/I^{-}$ is $+0.53 \ V,$ for $Ag^{+}/Ag$ is $+0.79 \ V,$ $Na^{+}/Na$ is $-2.71 \ V$ and for $Li^{+}/Li$ is $-3.04 \ V.$ Arrange the following ionic species in decreasing order of reducing strength: $I^{-}, Ag, Cl^{-}, Li, Na$

$E^o_{cell}$ for the cell: $Pt_{(s)} | H_{2(g)} | HCOOH_{(aq)} || CH_3COOH_{(aq)} | H_{2(g)} | Pt_{(s)}$ at $25^oC$ is ............ $V$. ($K_a$ of $HCOOH = 2.4 \times 10^{-4}$,$K_a$ of $CH_3COOH = 1.8 \times 10^{-5}$,$\log 2 = 0.3$,$\log 3 = 0.477$,$\frac{2.303RT}{F} = 0.059$ or $0.06$)

Give the method to determine the potential of any half-cell.

The standard oxidation potential of a calomel electrode is:

Consider the following cell:
$Zn_{(s)} \mid Zn^{2+}_{(1M)} \parallel KCl_{(sat)} \mid Hg_2Cl_{2(paste)} \mid Hg$
$E^{\circ}_{cell} = 1.007 \ V$ and $E^{\circ}_{calomel} = 0.242 \ V$
What is the standard potential of $Zn$ (in $V$)?