Which of the following statement(s) is(are) correct?

$A$ weak acid is titrated with a weak base. Consider the following statements regarding the $pH$ of the solution at the equivalence point.
$(i)$ $pH$ depends on the concentration of acid and base
$(ii)$ $pH$ is independent of the concentration of acid and base
$(iii)$ $pH$ depends on the $pK_{a}$ of acid and $pK_{b}$ of base
$(iv)$ $pH$ is independent of the $pK_{a}$ of acid and $pK_{b}$ of base
The correct statements are

If equivalent conductance of $1 \ M$ benzoic acid is $12.8 \ \Omega^{-1} \ cm^2 \ eq^{-1}$ and if the equivalent conductances of benzoate ion and $H^+$ ion at infinite dilution are $42$ and $288.42 \ \Omega^{-1} \ cm^2 \ eq^{-1}$ respectively,then its degree of dissociation is ............ $\%$

If the concentration of $OH^{-}$ ions is $10^{-7} \text{ gram ions/litre}$,what is the number of $OH^{-}$ ions in one litre of water?

For a $0.01 \ M \ HCN$ solution,the van't Hoff factor is $1.002$. What will be the acid dissociation constant $(K_a)$ for $HCN$?

$5 \ mL$ of $0.4 \ N$ $NaOH$ is mixed with $20 \ mL$ of $0.1 \ N$ $HCl$. The $pH$ of the resulting solution will be