Two solid metallic cuboids of dimensions $15 \mathrm{cm}\times 8 \mathrm{cm}\times 5 \mathrm{cm}$ and $20 \mathrm{cm}\times 5 \mathrm{cm}\times 4 \mathrm{cm}$, are melted together and recast into solid cubes each of side $5 \mathrm{cm}$. Find the number of solid cubes so formed.

A bucket is in the form of a frustum of a cone. If the height of the bucket is $16 \mathrm{cm}$ and the radii of the upper and lower ends are $18 \mathrm{cm} \& 6 \mathrm{cm}$ respectively, find the height of the cone of which the bucket is a part.

A bucket is in the form of a frustum of a cone. If the height of the bucket is $16 \mathrm{cm}$ and the radii of the upper and lower ends are $18 \mathrm{cm} \& 6 \mathrm{cm}$ respectively, find the capacity of the bucket (in decimal form).