[填空题]
The following diagram / gly47nvozp :shows h)saom* 0lm0uv//ycrt( zdv :triangle ABC and sector ACD of a circle with centre C.
/:v*z/ dm mvcu r0(0h)lsay to
$\mathrm{AC}=5 \mathrm{~cm}, \mathrm{BC}=8 \mathrm{~cm} $, the area of triangle $\mathrm{ABC}=10 \sqrt{3} \mathrm{~cm}^{2}$ .
1. Find AĈB.
2. Find the exact area of sector ACD.
