he 12 shapes in the Venn diagram shown to the right are described by the attributes of​ shape, size, and color. Let​ C, H, and T denote the respective sets of​ circular, hexagonal, and triangular shapes.​ Similarly, let​ S, L,​ R, and B denote the sets of​ small, large,​ red, and blue shapes. The set A contains the shapes that are small and not a​ triangle, so A=S∩T.