A solid is in the shape of a cone surmounted on a hemisphere, the radius of each of them being $3.5 \mathrm{cm}$ and the total height of the solid is $9.5 \mathrm{cm}$. Find the volume of the solid in cubic centimeters. (Use $\mathrm{\pi }=\frac{22}{7}$)

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 $k$ ?