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Find the given elements if matrix d:

The random variable x is the number of occurrences of an event over an interval of ten minutes. it can be assumed that the probability of an occurrence is the same in any two-time periods of an equal length. it is known that the mean number of occurrences in ten minutes is 5.3. the appropriate probability distribution for the random variable

Simplify. (-2)^-3 a. -8 b. -1/8 c. 1/8 d. 8