[填空题]
In a triangle $ \mathrm{ABC}$, $\mathrm{AB}=3 \mathrm{~cm}$, $\mathrm{BC}=5 \mathrm{~cm}$ and $\mathrm{ACB}=\frac{\pi}{6}$
1. Find, to three significant figures, the two possible lengths of [AC]
2. Find the difference between the areas of the two possible triangles A B C .
