Chromium metal crystallises witha body-centred cubic lattice.The length of the unit cell edge is found to be 287pm.Calculate the atomic radius.What would be the density of chromium in $g/cm^3$?

Question

$\begin{array}{1 1}7.30gcm^{-3}\\6.30gcm^{-3}\\4.30gcm^{-3}\\3.30gcm^{-3}\end{array}$