$5)$ If an X$-$ray diffraction pattern for a powder sample of Ni is measured using a conventional diffractometer. Six diffraction peaks corresponding to $(111),(200),(220),(311),(222),$ and $(400)$ planes were obtained. Compute the Lorentz$-$polarization factor using Cu$-$Ka radiation $\backslash$lambda $=0\mathrm{.}1542$ nm$.($crystal system: FCC and a $=0\mathrm{.}2479$ nm$).(10$ Points$)$