$A$ running track is in the shape of a circular ring. The difference of its outer circumference and inner circumference is $44\,m$. Then,the width of the track is $\ldots \ldots \ldots \ldots\,m$.

If the area of a circle is $154 \, cm^2$,then its perimeter (circumference) is (in $cm$):

$A$ car has two wipers which do not overlap. Each wiper has a blade of length $25 \, cm$ sweeping through an angle of $115^{\circ}.$ Find the total area cleaned at each sweep of the blades. [use $\pi=\frac{22}{7}$]

The circumference of a circular ground is $352\, m$. Find the area of the ground (in $m^2$).

The maximum area of a triangle inscribed in a semicircle having radius $10 \, cm$ is $\ldots \ldots \ldots \, cm^2$.

$A$ field is in the shape of an equilateral triangle in which the length of each side is $70\, m$. $A$ cow is tethered at one of its vertices by a $5\, m$ long rope. Find the area of the region in the field in which the cow can graze. $(\pi = 3.14)$ (in $m^2$)