In a circle of radius $42\, cm,$ an arc subtends an angle of $72^{\circ}$ at the centre. The length of the arc is.....$cm$ (in $.8$)?

The height of an equilateral triangle whose perimeter is $24 \, cm$ is

Among a square of perimeter $44\, cm$ and a circle of circumference $44\, cm,$ which figure has a larger area and by how much?

Two circles touch each other externally. The sum of their areas is $130 \pi \text{ cm}^2$ and the distance between their centres is $14 \text{ cm}$. The radius of the smaller circle is . . . . . . $\text{cm}$.

The length of a rectangular hall is $5\, m$ more than its breadth. The area of the hall is $750\, m^{2}$. The length of the hall is.........$m$

In the given figure,$ABCD$ is a square. $EFGH$ is a square formed by joining the midpoints of the sides of $ABCD$. $LMNO$ is a square formed by joining the midpoints of the sides of $EFGH$. $A$ circle is inscribed inside $LMNO$. If the area of the circle is $38.5 \text{ cm}^2$,then what is the area (in $\text{cm}^2$) of square $ABCD$?