1. (a) What arc the intcrplanar spacings d for the (100), ( ll O), and (111) planes of Al ( a4.05 A)?
(b) What are the Miller ind ices of a plane tha t intercepts the x-axis at a, the y-axis at 2a, and the z-axis at 2a?
2. Show that the cla ratio for an ideal hexagonal close-packed structure is (8/3{'2 =1.633. If cla is significantly larger than this value, the crystal structure may be thought of as composed of planes of closely-packed atoms, the planes being loosely stacked.