Fundamental type of lattice

Crystal lattice can be carried into them selves by the lattice translations (T) and by other symmetry operations [Rotation about an axis (1, 2, 3, 4, and 6-fold), Reflection at a plane, and Inversion through a point].
We say that a crystal has n-fold axis of rotation if rotation through an angle (?=2?/n) carry the lattice into itself. Lattice can be found such that 1, 2, 3, 4, and 6-fold rotation axes carry the lattice into itself, corresponding to rotations by ?=2?, 2?/2, 2?/3, 2?/4,and 2?/6 radians.
We say that a crystal has n-fold axis of rotation if rotation through an angle (?=2?/n) carry the lattice into itself. Lattice can be found such that 1, 2, 3, 4, and 6-fold rotation axes carry the lattice into itself, corresponding to rotations by ?=2?, 2?/2, 2?/3, 2?/4,and 2?/6 radians.
We say that a crystal has n-fold axis of rotation if rotation through an angle (?=2?/n) carry the lattice into itself. Lattice can be found such that 1, 2, 3, 4, and 6-fold rotation axes carry the lattice into itself, corresponding to rotations by ?=2?, 2?/2, 2?/3, 2?/4,and 2?/6 radians.
We say that a crystal has n-fold axis of rotation if rotation through an angle (?=2?/n) carry the lattice into itself. Lattice can be f
Q/Find all the possible elements symmetry for the SC.We cannot find a lattice that goes into itself under other rotation, such as 2?/7, 2?/5.This means that a 5- fold axis cannot exist in a periodic lattice. Explain why?.