Fe has two solid phases at standard pressures. $-Fe$ is a body centered cubic phase

$($S$.$G$.$ Im $\frac{?}{\text{b}\text{a}\text{r}}(3)m)$ with $a=0\mathrm{.}28665nm.-Fe$ is a face centered cubic phase $($S$.$G$.$

$F\frac{m}{b}ar(3)m)$ with $a=0\mathrm{.}36469nm$

a$.$ Calculate the powder diffraction patterns for $-Fe$ and $-$Fe using VESTA.

$(2$ pts$)$

b$.$ Using $CuKa{a}_1(-0\mathrm{.}154059nm)$ and $\frac{1}{d^2}=\frac{h^2+k^2+t^2}{a^2},$ calculate the

diffraction angle for bec$(110)$ and fec$(111)(2$ pts$)$

c$.$ Create pictures of the bec$(110)$ and the fco$(111)$ surfaces using VESTA. $(2$

pts$)$