[问答题]
Let $w=2 e^{\mathrm{i} \frac{2 \pi}{3}}$ .
1. 1. Write w, $w^{2}$ and $w^{3}$ in the form $a+b \mathrm{i}$ where a, $b \in \mathbb{R}$ .
2. Draw w, $w^{2}$ and $w^{3}$ on an Argand diagram.
2. Find the smallest integer k>3 such that $w^{k}$ is a real number.
