Final answer:
Events A and B cannot be disjoint since the sum of their probabilities exceeds 1, which indicates that they are not mutually exclusive and may have some overlap.
Step-by-step explanation:
To determine whether events A and B are disjoint, also known as mutually exclusive, you would need to know if they can occur at the same time. Disjoint events cannot happen simultaneously, meaning if one event occurs, the other cannot. In this case, if the probability of event A is P(A)=0.5, and the probability of event B is P(B)=0.7, we cannot determine if they are disjoint based solely on their individual probabilities.
However, we can say that events A and B cannot be disjoint if the sum of their probabilities exceeds 1, which would violate the fundamental rules of probability. Since the sum of probabilities P(A) and P(B) is 0.5 + 0.7 = 1.2, which is greater than 1, A and B cannot be disjoint. They must have some overlap, meaning there's a non-zero probability that both A and B can occur simultaneously.