$A$ $pH$ of $7$ signifies

If $[H_3O^+]$ of a solution is $1 \times 10^{-4} \text{ M}$, what is the value of $pOH$ at $298 \text{ K}$?

The $pH$ of $D_2O$ and $H_2O$ at $298 \ K$ is

The $pH$ of water at $25\,^oC$ is nearly

Observe the following solutions:
$I$. Black coffee
$II$. $0.2 \ M \ NaOH$
$III$. Lemon juice
$IV$. Lime water
$V$. Human saliva
$VI$. Tomato juice
The number of solutions having $pH$ range of $1-7$ and $7-14$,in the above list,is respectively.

The $pH$ of a solution is $9.5$. The solution is