The cross-section of a canal is a trapezium in shape. If the canal is $10 \mathrm{m}$ wide at the top, $6 \mathrm{m}$ wide at the bottom and the area of cross-section is $72 \mathrm{sq}.\mathrm{m}$, determine its depth in metre.

The three sides of a triangle are $15 cm, 36 cm, and 39 cm$ long. A small triangle is formed by joining the mid points of the three sides of this triangle. The area of small triangle will be_____ $c{m}^2$  

In $△ABC, AD$ is the median and $G$ is a point on $AD$ such that $AG:GD=2:1$. Then area $(△BDG):$area $(△ABC)$ is equal to:

The length of rectangle is $80\%$ of diagonal of square of area $1225 {\mathrm{m}}^2$, then find area of rectangle, if it's perimeter is $94\sqrt{2} \mathrm{m}$.

What is the area of this trapezoidal garden (All measurements are in cm)? 

1. $60$ sq.cm
2. $180$ sq.cm
3. $210$ sq.cm 
4. $240$ sq.cm