Find the perimeter (in $cm$) of a semicircle of radius $28\, cm$.

Find the area of an isosceles right-angled triangle whose hypotenuse is $8\, cm$.

In the given figure,$OP = PQ = 14 \, cm$ and semicircles are drawn on $OP$,$PQ$,and $OQ$ as diameters. Then,the perimeter of the shaded area is . . . . . . $cm$.

The area of a field in the shape of a trapezium is $1440 \, m^2$. The perpendicular distance between its parallel sides is $24 \, m$. If the ratio of the parallel sides is $5:3$, the length of the larger parallel side is ....... $m$.

$A$ parallelogram has sides $60\, cm$ and $40\, cm$ and one of its diagonals is $80\, cm$ long. Its area is

$A$ tank is $25 \ m$ long,$12 \ m$ wide and $6 \ m$ deep. The cost of plastering its walls and bottom at $75 \ paise/m^2$ is (in $Rs.$)