Identify the good conductor of electricity from following band gap energy values of solids.

Which from following is NOT an example of amorphous solid?

Calculate the molar mass of metal having density $$9.3 \mathrm{~g} \mathrm{~cm}^{-3}$$ that forms simple cubic unit cell. $$\left[\mathrm{a}^3 \cdot \mathrm{N}_{\mathrm{A}}=22.6 \mathrm{~cm}^3 \mathrm{~mol}^{-1}\right]$$

Find the radius of an atom in fcc unit cell having edge length $$405 \mathrm{pm}$$.