A solid is in the form of a cylinder with hemispherical ends. The total height of the solid is $19 cm$ and the diameter of the cylinder is $7 cm$. Find the total surface area of the solid. ( Use $\mathrm{\pi }=\frac{22}{7}$)

In the adjoining figure, $AOBCA$ represents a quadrant of a circle of radius $3.5 cm$ with centre $O$. Calculate the area of the shaded portion. (Use $\mathrm{\pi }=\frac{22}{7}$)

Find the area of the shaded region (in sq. cm) if the radius of each of the circles is $1 cm$.

A right elliptical cylinder full of petrol has its widest elliptical side $2.4 m$ and the shortest $1.6 m$. Its height is $7 m$. Find the time required to empty half the tank through a hose of diameter $4 cm$ if the rate of flow of petrol is $120 m/min.$

Find the area of the trapezium $ABCD$

$PQRS$ is the diameter of a circle of radius $6 cm$. The lengths $PQ, QR$ and $RS$ are equal. Semi-circles are drawn with $PQ$ and $QS$ as diameters as shown in the figure alongside. Find the ratio of the area of the shaded region to that of the unshaded region.