The ratio of the $3$ angles of a quadrilateral is $13: 9: 5$. The value of the $4^{th}$ angle of the quadrilateral is $36^{\circ}$. What is the difference between the largest and the second smallest angles of the quadrilateral? (in $^{\circ}$)

Find the area of a triangle in which base is $1.5\, m$ and height is $75\, cm$? (in $sq. cm.$)

If the length and breadth of a rectangular plot are increased by $50 \%$ and $20 \%$ respectively,then the new area is how many times the original area?

In the figure,$DE \parallel BC$. If $DE = 3 \text{ cm}$,$BC = 6 \text{ cm}$,and the area of $\Delta ADE = 15 \text{ cm}^2$,then the area of $\Delta ABC$ is ............ $\text{cm}^2$.

The area of a parallelogram is $72 \, cm^{2}$ and its altitude is twice the corresponding base. The length of the base is.....$cm$.

The perimeter of a square is equal to twice the perimeter of a rectangle whose dimensions are: length $8 \, cm$ and breadth $7 \, cm$. What is the circumference of a semicircle whose diameter is equal to the side of the square? (in $cm$) (Rounded off to two decimal places)