Why does copper not replace hydrogen from acids?

For the reaction $M^{+n}_{(aq)} + ne^{-} \rightarrow M_{(s)}$,if the standard reduction potentials of elements $M_1, M_2$,and $M_3$ are $-0.34 \ V$,$-3.05 \ V$,and $-1.66 \ V$ respectively,what is the order of their reducing strength?

The standard electrode potential for a $Daniell$ cell is $1.1 \ V$. Calculate the standard Gibbs energy for the reaction: $[Zn_{(s)} + Cu^{2+}_{(aq)} \rightarrow Zn^{2+}_{(aq)} + Cu_{(s)}]$

For the cell reaction:
$2 Fe^{3+}_{(aq)} + 2 I^{-}_{(aq)} \rightarrow 2 Fe^{2+}_{(aq)} + I_{2(aq)}$
$E^{\ominus}_{cell} = 0.24 \ V$ at $298 \ K$. The standard Gibbs energy $(\Delta_r G^{\ominus})$ of the cell reaction in $kJ \ mol^{-1}$ is:
[Faraday constant $F = 96500 \ C \ mol^{-1}$]

The $E^{\circ}_{cell}$ of $Cu_{(s)} | Cu^{2+}_{(1M)} || Ag^{+}_{(1M)} | Ag_{(s)}$ is $0.647 \ V$. Calculate the $E^{\circ}_{Ag}$ if $E^{\circ}_{Cu}$ is $0.153 \ V$. (in $V$)

If the $\Delta G$ of a cell reaction $AgCl + e^- \to Ag + Cl^{-}$ is $-21.20 \ kJ$,the standard e.m.f. of the cell is ............ $V$.