The American Red Cross must track their supply and demand for various blood types. They estimate that about 45% of the U.S. population has Type O blood, 40% Type A, 11 % Type B, and the rest Type AB-
a) If someone volunteers to give blood, what is the probability that this donor:
i) Has Type AB blood?
ii) Has Type A or Type B blood?
iii) Is not Type O?
b) Among four potential donors, what is the probability that:
i) All are Type O?
ii) None have Type AB blood?
iii) Not all are Type A?
iv) At least one person is Type B?