Write a program capable of determining the angle between any two crystallographic planes (h1k1l1 and h2,k2,l2) which will work for any crystal system (the program should be written for the triclinic system). For a particular crystal you will be given the lattice parameters, a,b,c and interaxial angles , , and . Test that your program works by comparing against the table of interplanar angles for cubic crystals provided below. (in excel)