Blood types:The blood type O negative is called the "universal donor" type, because it is the only blood type that may safely be transfused into any person. Therefore, when someone needs a transfusion in an emergency and their blood type cannot be determined, they are given type O negative blood. For this reason, donors with this blood type are crucial to blood banks. Unfortunately, this blood type is fairly rare; according to the Red Cross, only7

%

of U.S. residents have type O negative blood. Assume that a blood bank has recruited19

donors. Round the answers to four decimal places.

Part 1 of 3

(a) What is the probability that two or more of them have type O negative blood?The probability that two or more of them have type O negative blood is

.

Part 2 of 3

(b) What is the probability that fewer than four of them have type O negative blood?The probability that fewer than four of them have type O negative blood is

.

Part 3 of 3

(c) Would it be unusual if none of the donors had type O negative blood?It

(Choose one)

be unusual if none of the donors had type O negative blood since the probability is

.