\[Дано:\]
\[\sin{\angle A} = 0,4;\]
\[AC = 18\ см;\]
\[BC = 6\ см.\]
\[Решение:\]
\[\frac{\text{AC}}{\sin{\angle B}} = \frac{\text{BC}}{\sin{\angle A}}\]
\[\frac{18}{\sin{\angle B}} = \frac{6}{0,4}\]
\[\sin{\angle B} = \frac{18 \bullet 0,4}{6} = 1,2.\]
\[Ответ:\ \ не\ существует.\]