A1:Hexagonal Crystal Structures(Chapter 2) 7.5 points a) Draw in the following unit cells of a hexagonal close packed crystal structure (respectively three unit cells are displayed for visualization of the crystal symmetry) the respectively given directions and planes,and please indicate them clearly.Please keep in mind,that in each case specific directions and planes are addressed,whose position in the unit cell is defined unambiguously.(4 Points) [1120] [2i3] 木C a3 a3 a2 a2 K a1 k a1 ī00) 122) 个C a a3 a2 a2 a1 a b) Which slip system is the most important slip system and the most important twinning system in the hexagonal dense packed crystal lattice?(2 points) 9 Discuss the twinning of hexagonal materials in dependence of the c/a-ration in case of compression perpendicular to the c-axis.(1.5 points)1 A1: Hexagonal Crystal Structures (Chapter 2) 7.5 points a) Draw in the following unit cells of a hexagonal close packed crystal structure (respectively three unit cells are displayed for visualization of the crystal symmetry) the respectively given directions and planes, and please indicate them clearly. Please keep in mind, that in each case specific directions and planes are addressed, whose position in the unit cell is defined unambiguously. (4 Points) [11 20] [1 2 1 3] (1 100) (11 22) b) Which slip system is the most important slip system and the most important twinning system in the hexagonal dense packed crystal lattice? (2 points) c) Discuss the twinning of hexagonal materials in dependence of the c/a-ration in case of compression perpendicular to the c-axis. (1.5 points)