$\sqrt{2}\ \text{cm}$\sqrt{2}\ \text{cm}

$\displaystyle \frac{\sqrt{3}}{2} \ \text{cm}$\displaystyle \frac{\sqrt{3}}{2} \ \text{cm}

$\sqrt{3}\ \text{cm}$\sqrt{3}\ \text{cm}

$2\ \text{cm}$2\ \text{cm}