$A$ shot-put is a metallic sphere of radius $4.9 \, cm$. If the density of the metal is $7.8 \, g/cm^3$,find the mass of the shot-put. (in $, kg$)

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 $, cm$)

$A$ hemispherical bowl made of brass has an inner diameter of $10.5 \, cm$. Find the cost of tin-plating it on the inside at the rate of $Rs. 16$ per $100 \, cm^2$.

$A$ village,having a population of $4000$,requires $150$ litres of water per head per day. It has a tank measuring $20 \,m \times 15 \,m \times 6 \,m$. For how many days will the water of this tank last?

$A$ cubical box has each edge $10\, cm$ and another cuboidal box is $12.5\, cm$ long,$10\, cm$ wide and $8\, cm$ high. Which box has the greater lateral surface area and by how much (in $, cm^2$)?

The height of a cone is $16 \, cm$ and its base radius is $12 \, cm$. Find the curved surface area and the total surface area of the cone (Use $\pi = 3.14$). (in $, cm^2$)