The volume of a right circular cone is $9856 \, cm^3$. If the diameter of the base is $28 \, cm$,find the slant height of the cone. (in $, cm$)

Find the surface area of a sphere of radius $10.5 \, cm$.
Assume $\pi = \frac{22}{7}$. (in $, cm^{2}$)

$A$ hemispherical bowl has a radius of $3.5\, cm$. What would be the volume of water it would contain (in $, cm^{3}$)?

Find the lateral or curved surface area of a closed cylindrical petrol storage tank that is $4.2\, m$ in diameter and $4.5\, m$ high. $\left[\text{Assume } \pi = \frac{22}{7}\right]$ (in $, m^2$)

$A$ wall of length $10\, m$ was to be built across an open ground. The height of the wall is $4\, m$ and thickness of the wall is $24\, cm$. If this wall is to be built up with bricks whose dimensions are $24\, cm \times 12\, cm \times 8\, cm$,how many bricks would be required?

Mary wants to decorate her Christmas tree. She wants to place the tree on a wooden box covered with coloured paper with a picture of Santa Claus on it (see figure). She must know the exact quantity of paper to buy for this purpose. If the box has length,breadth,and height as $80 \, cm$,$40 \, cm$,and $20 \, cm$ respectively,how many square sheets of paper of side $40 \, cm$ would she require?