What does the number x equal from the equation?

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

An investment decreases in value by 30% in the first year and decreases by 40% in the second year. what is the percent decrease in percentage in the investment after two years

Which of the following represents the length of a diagonal of this trapezoid?