A wooden article was made by scooping out a hemisphere from each end of a cylinder, as shown in the figure. If the height of the cylinder is $20 \mathrm{cm}$ and its base is of diameter $7 \mathrm{cm}$, find the total surface area of the article when it is ready.

If total surface area of the article is $k {\mathrm{cm}}^2$, then find $k$ ?

 

If the volume of the water left in the tub is $k {\mathrm{cm}}^3$, then find $k$ ?

If total surface area of the remaining solid is $k {\mathrm{cm}}^2$, then find $k$ ? 

If total surface area of the remaining solid is $k {\mathrm{cm}}^2$, then find $k$ ? (Use $\mathrm{\pi }=\frac{22}{7}$)

If volume of the remaining solid is $k {\mathrm{cm}}^3$, then find $k$ ?

A metallic cylinder has radius $3 \mathrm{cm}$ and height $5 \mathrm{cm}$. To reduce its weight, a conical hole is drilled in the cylinder. The conical hole has a radius of $\frac{3}{2} \mathrm{cm}$ and its depth is $\frac{8}{9} \mathrm{cm}$. Calculate the ratio of the volume of metal left in the cylinder to the volume of metal taken out in conical shape.

If the ratio of the volume of metal left in the cylinder to the volume of metal taken out in conical shape is $k:2$, then find $k$?

The given figure represents a solid consisting of a cylinder surmounted by a cone at one end and a hemisphere at the other. Find the volume of the solid.

If the volume of the solid is $k {\mathrm{cm}}^3$, then find $k$ ? (Use $\mathrm{\pi }=\frac{22}{7}$)

After finding above quantities, if total surface area of the remaining piece is $k {\mathrm{cm}}^2$, then find $k$ ? (Use $\mathrm{\pi }=\frac{22}{7}$)