A circle is inscribed in a square of side 56 cm. Find the maximum area of circle.

Find the area of the shaded region.

The ratio of the diameters of two circles is $4: 5$. Find the ratio of their circumference.

A field is in the form of parallelogram whose base is $42000 cm$ and altitude is $360 cm$. Find the cost of watering it at $50 paise per sq. m$.

Find the cost of painting a wall with dimensions $25 m by 9 m$ at the rate of $₹120$ per square metre.

In the adjoining figure, a rectangular ground is $90 m$ long and $32 m$ broad. In the middle of the ground there is a circular tank of radius $14 metres$. Find the cost of turfing the remaining portion at the rate of $₹2.50$per square metre.

Two circles have diameters in the ratio $2: 5$. Find the ratio of their circumferences.

A large pizza has a circumference of $154 cm$. Which of the sides listed below could belong to the smallest square box capable of holding a large pizza?