$10^{-6} \ M \ HCl$ is diluted $100$ times. Its $pH$ is

The $pH$ value of $0.1 \ M \ NaOH$ solution is (given that the ionic product of water $K_w = [H^{+}] [OH^{-}] = 10^{-15}$)

Given below are two statements:
Statement-$I$: $pH$ of a $1.0 \times 10^{-8} \ M$ solution of $HCl$ is $8$ at $25^{\circ} C$.
Statement-$II$: $HCl$ is a strong acid and negative log of $H^{+}$ concentration is called $pH$.
In the light of the above statements,choose the most appropriate answer from the options given below:

Which of the following solutions will have a $pH$ close to $1.0$?

At $27^{\circ} C$, $100 \ mL$ of $0.5 \ M$ $HCl$ is mixed with $100 \ mL$ of $0.4 \ M$ $NaOH$ solution. To this resultant solution, $800 \ mL$ of distilled water is added. What is the $pH$ of the final solution?

Assuming that $Ba(OH)_{2}$ is completely ionised in aqueous solution under the given conditions,the concentration of $H_{3}O^{+}$ ions in $0.005 \, M$ aqueous solution of $Ba(OH)_{2}$ at $298 \, K$ is $..... \times 10^{-12} \, mol \, L^{-1}$. (Nearest integer)