Body diagonal of a cube is $866 \mathrm{pm}$. Its edge length would be 

The edge of a cube is $8 \mathrm{cm}$ .What is the total surface area of the cube?

The curved surface area of a hemisphere with radius $7 \mathrm{cm}$ is: 

(Take$\mathrm{\pi }=\frac{22}{7}$)

What is the volume of the sphere whose diameter is $42 \mathrm{cm}?$

(Take $\pi =\frac{22}{7}$)