cd homework_7 mkdir dir_0 dir_1 dir_2 cp a.txt dir_0/a0.txt cp b.txt dir_0/b0.txt cp c.txt dir_0/c0.txt cp a.txt dir_1/a1.txt cp b.txt dir_1/b1.txt cp c.txt dir_1/c1.txt cp a.txt dir_2/a2.txt cp b.txt dir_2/b2.txt cp c.txt dir_2/c2.txt