find PH at equivalence point

Volume of NaOH$=16\mathrm{.}05mL$

Concentration of NaOH$=0\mathrm{.}1M$

volume of acetic acid $=20mL$

Concentration of acetic acid $=0\mathrm{.}8025M$

$k_a=1,74{10}^{-5}$