A, square close packing in two dimensions each sphere have corrdination number 4, as shown below
B. Hexagonal close packing in two dimensions each sphere have coordination number 6 as shown below and creates a triangular void
C. Hexagonal close packing in 3 dimensions is a repeated pattern of sphere in alternate layer also known as ABAB pattern
D. Cubic close packing in a 3 dimensions is a repeating pattern of sphere in every fourth layer
