Determine the $pH$ during the titration of $16\mathrm{.}3mL$ of $0\mathrm{.}337M$ nitric acid by $7\mathrm{.}32{10}^{-2}M$ barium hydroxide at

the following points:

$(1)$ Before the addition of any barium hydroxide

$(2)$ After the addition of $18\mathrm{.}8mL$ of barium hydroxide

$(3)$ At the equivalence point

$(4)$ After adding $46\mathrm{.}1mL$ of barium hydroxide