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

Area of a sector of a circle of radius $36 \, cm$ is $54 \pi \, cm^{2}$. Find the length of the corresponding arc of the sector (in $cm$). (in $\pi$)

As shown in the diagram, rectangle $ABCD$ is a metal sheet in which $CD = 20 \, cm$ and $BC = 14 \, cm$. From it, a semicircle with diameter $\overline{BC}$ and a sector with centre $A$ and radius $AD$ is cut off. Find the area of the remaining sheet in $cm^2$.

Find the area of a sector of a circle of radius $28 \,cm$ and central angle $45^{\circ}$. (in $cm^{2}$)

The circumference of a circle is $176 \, cm$. Find its radius in $cm$.

$A$ cow is tied with a rope of length $14 \, m$ at the corner of a rectangular field of dimensions $20 \, m \times 16 \, m$. Find the area of the field in which the cow can graze. (in $m^2$)