Answer: Blood type will be A when event "A" happened and event "B" did not happen. Blood type will be B when event "A" did not happened and event "B" happened. Blood type will be AB when both events happened and blood type will be O when both events did not happen.
Step-by-step explanation:
S={AntiA reacts; AntiA does not react; AntiB reacts; AntiB does not react}
If AntiA reacts and AntiB reacts = AB (A∩B)
If AntiA does not react and AntiB does not react= O (A'∩B')
If AntiA reacts and AntiB does not react= A (A∩B')
If AntiA does not react and AntiB reacts= B (A'∩B)
