An element crystallises in a structure having fcc unit cell with edge length of 200pm.Calculate its density .If 200g of this element contains $24\times 10^{23}$ atoms.

Question

$\begin{array}{1 1}41.67gcm^{-3}\\51.67gcm^{-3}\\61.67gcm^{-3}\\31.67gcm^{-3}\end{array}$