Since it's a right triangle, use the tanget ratio:

\(\displaystyle{\tan{{\left(\angle\right)}}}=\frac{{\overline{{{o}{p}{p}}}}}{{\overline{{{a}{d}{j}}}}}\)

Substitute values from the given:

\(\displaystyle{{\tan{{65}}}^{\circ}=}\frac{{250}}{\overline{{B}}}\)

Isolate \(\displaystyle\overline{{B}}\):

\(\displaystyle\overline{{B}}=\frac{{250}}{{{\tan{{65}}}^{\circ}}}\)

\(\displaystyle\overline{{B}}\approx{116.6}\) m

\(\displaystyle{\tan{{\left(\angle\right)}}}=\frac{{\overline{{{o}{p}{p}}}}}{{\overline{{{a}{d}{j}}}}}\)

Substitute values from the given:

\(\displaystyle{{\tan{{65}}}^{\circ}=}\frac{{250}}{\overline{{B}}}\)

Isolate \(\displaystyle\overline{{B}}\):

\(\displaystyle\overline{{B}}=\frac{{250}}{{{\tan{{65}}}^{\circ}}}\)

\(\displaystyle\overline{{B}}\approx{116.6}\) m