Find the area of a polygon $ABCDEFG$ given below:

Find the area of the following polygon:

Find the area of the following polygon:

Find the area of the shaded region in the following figure:

The cross section of a railway tunnel is in the shape of trapezium. The tunnel is $8 m$ wide at the top and $12 m$ wide at the bottom and the area of the cross section is $100 m^2$. Determine the height of the tunnel.

If the diagonals of a rhombus are $7 \mathrm{cm}$ and $12 \mathrm{cm}$, then the area of the rhombus will be _____ .

If side $\mathrm{a}$ if a square is halved, then the area will be _____ .