A right circular cylinder of length $35 ft$ and radius $5 ft$. From the piece, a rectangular parallelepiped of the square base is to be formed. How many cubic feet of wood will remain? How much wood was spent from the log?

The height of a hollow circular cylinder open at both ends is $36 cm$. The thickness of the cylinder is $1 cm$ and the external diameter is $10 cm$. If the area of the whole surface of the hollow cylinder is $k c{m}^2$, then find the value of $k$ (correct up to two decimal places).