Question: BLOOD TYPING Human blood is classified by the presence or absence of three main antigens (A, B, and Rh). When a blood specimen is typed, the presence of the A and/or B antigen is indicated by listing the letter A and/or the letter B. If neither the A nor B antigen is present, the letter O is used. The presence or absence of the Rh antigen is indicated by the symbols + or - , respectively. Thus, if a blood specimen is classified as AB+, it contains the A and the B antigens as well as the Rh antigen. Similarly, O blood contains none of the three antigens. Using this information, determine the sample space corresponding to the different blood groups.