If the perimeter of an equilateral triangle is $12\, m$,then find its area.

In a quadrilateral $ABCD$,the sides $AB, BC, CD, DA$ measure $20\, m, 13\, m, 17\, m$ and $10\, m$ respectively,and the diagonal $AC$ is $21\, m$. The area of the quadrilateral is ........ $m^2$.

The area of a rectangular field is $27000 \, m^2$. The ratio of its length and breadth is $6:5$. The length and breadth of the field are respectively:

Three metal cubes with edges $6\, cm$,$8\, cm$,and $10\, cm$ respectively are melted together and formed into a single cube. Find the side of the resulting cube (in $cm$).

The sides of a triangle are $6\, cm$,$11\, cm$,and $15\, cm$. The radius of its incircle is

$A$ wire when bent in the form of a circle encloses an area of $1386 \, cm^2$. What will be the enclosed area when the same wire is bent into the form of an equilateral triangle?