Which of the following mixtures of gases does not obey Dalton's law of partial pressure?

Atmolysis is a process of

Calculate the partial pressure exerted by dioxygen from a mixture of $32 \ g$ $O_2$,$80 \ g$ $Ar$ (molar mass $40 \ g/mol$) and $4 \ g$ dihydrogen $(P_{\text{total}} = 10 \ bar)$. (in $bar$)

If $N_2, O_2, H_2$,and $He$ gases are filled separately in four car tubes at the same pressure,which gas will diffuse first?

When a gas is heated at constant pressure from $20\,^oC$ to $40\,^oC$,its volume:

$A$ vessel of $2.461 \ L$ contains a mixture of $0.3 \ mol$ of $N_2$,$0.5 \ mol$ of $He$,and $6.2 \ mol$ of $O_2$ at $27 \ ^oC$. What is the partial pressure of $N_2$ in the mixture in $atm$?