Area of an equilateral triangle$=$____________$(\mathrm{side}{)}^2$.

A paper is in the form of a rectangle $\mathrm{DARK}$ in which $\mathrm{DA}=30 \mathrm{cm}$ and $\mathrm{KD}=21 \mathrm{cm}$. A semicircular portion with $\mathrm{AR}$ as diameter is cut-off. Find the area of the remaining part.

Find the area of the shaded region, if $\mathrm{PAST}$ is a square of side $14 \mathrm{cm}$ and $\mathrm{ALS}$ and $\mathrm{PLT}$ are semicircles.

Find the are of the hexagon $\mathrm{TAGORE},$ if $\mathrm{TO}=9 \mathrm{cm}, \mathrm{TS}=7 \mathrm{cm}, \mathrm{TH}=6 \mathrm{cm}, \mathrm{TF}=4 \mathrm{cm}, \mathrm{TB}=2 \mathrm{cm}, \mathrm{AB}=3 \mathrm{cm}, \mathrm{GH}=5 \mathrm{cm}, \mathrm{SR}=2 \mathrm{cm}$ and $\mathrm{EF}=4 \mathrm{cm}$