$7.($a$)[4$ pts$]$ Draw and identify one example of primary slip systems in the below crystals and name the slip systems $($plane and directions$)$ you draw using the Miller convention, respectivelv. Mark the origin and axis.

$($b$)[3$ pts$]$ Discuss the difference in the plasticity $($slip under shear stress$)$ between two crystals. Which one can slip easily? and why?

$($