Final answer:
The provided question about the probability of tsunamis cannot be answered without additional information. For mutually exclusive events, the probability of both occurring is zero. The binomial and Poisson distributions can be used to calculate the probability of a certain number of occurrences of an event over time.
Step-by-step explanation:
The question that asks about the probability none of the tsunamis are nine meters or higher appears to be missing crucial information such as the probability of a tsunami being nine meters or higher or the total number of tsunamis being considered. Without this information, we cannot calculate the correct probability. The question might involve concepts from probability theory, a branch of mathematics that deals with the likelihood of various outcomes.
Regarding mutually exclusive events (such as H and D), if P(H) = .25 and P(D) = .15, the probability of both events H and D occurring simultaneously, denoted as P(HD), is 0 because by definition, mutually exclusive events cannot occur at the same time. For calculating the probability of an event happening a certain number of times over a period, such as low seismic activity in 5 of the next 100 days, we would use the binomial distribution or the Poisson distribution. These distributions help us to compute probabilities for a number of occurrences of an event when we know the event's likelihood or rate of occurrence.