In a swimming pool measuring $90\, m$ by $40\, m$,$150$ men take a dip. If the average displacement of water by a man is $8\, m^3$,what will be the rise in water level? (in $cm$)

The length of a rectangle is twice its breadth. If its length is decreased by $5\, cm$ and breadth is increased by $5\, cm$,the area of the rectangle is increased by $75\, cm^2$. Then the length of the rectangle is......$cm$.

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

The circumference of a circular field is $440 \, m$. $A$ circular path of $10 \, m$ width runs around the outside of the field. Find the cost of gravelling the path at the rate of $70 \, \text{paise}$ per square metre? (in $Rs.$)

$A$ figure consists of a square of side '$a$' $m$ with semi-circles drawn on the outside of the square. The area (in $m^{2}$) of the figure so formed will be

In the given figure,$ABCD$ is a square of side $14 \ cm$. $E$ and $F$ are mid-points of sides $AB$ and $DC$ respectively. $EPF$ is a semicircle whose diameter is $EF$. $LMNO$ is a square. What is the area (in $cm^2$) of the shaded region?