Find the area of the equilateral triangle having length of each side $50\, cm$.

$A$ field in the form of a parallelogram has sides $60 \, m$ and $40 \, m$ and one of its diagonals is $80 \, m$ long. Find the area of the parallelogram.

Find the area and the perimeter of a regular hexagon having length of each side $12\,cm$.

In a quadrilateral $ABCD$,$AB = 29 \, cm$,$BC = 35 \, cm$,$CD = 14 \, cm$,$DA = 50 \, cm$ and $AC = 48 \, cm$. Find its area. (in $, cm^2$)

Find the area of a triangle,two sides of which are $15\,cm$ and $28\,cm$ and the perimeter is $84\,cm$. (in $,cm^2$)

In quadrilateral $ABCD$, one of its diagonals $AC$ measures $20 \, cm$. The altitudes on $AC$ from vertices $B$ and $D$ are $8 \, cm$ and $12 \, cm$ respectively. Find the area of quadrilateral $ABCD$ in $cm^2$.