If the surface area of a sphere is $346.5 \, cm^{2},$ then its radius is.......$cm$
$\left[\text{taking } \pi = \frac{22}{7}\right]$

The base of a $10\, cm$ high solid cylinder is a semi-circle of radius $7\, cm$. Its total surface area (in $cm^2$) is (Use $\pi = \frac{22}{7}$)

If the radius of a sphere is doubled,then its volume is increased by (in $\%$)

$A$ conical cup is filled with ice cream. The ice cream forms a hemispherical shape on its open top. The radius of the hemispherical part is $7 \, cm$. The radius of the hemispherical part equals the height of the cone. Then the volume of the ice cream is $...... cm^3$. $\left[\pi=\frac{22}{7}\right]$

If the heights of two cones are in the ratio $1:5$ and their diameters are in the ratio $5:6$,what is the ratio of their volumes?

How many bricks are required to build a $15\, m$ long,$3\, m$ high,and $50\, cm$ thick wall,if each brick measures $25\, cm \times 12\, cm \times 6\, cm$?