What is the third term in sequence a(n)=3/2(-2)n-1

The length of triangle base is 26. a line, which is parallel to the base divides the triangle into two equal area parts. find the length of the segment between triangle legs.

Monthly water bills for a city have a mean of $108.43 and a standard deviation of $32.09. find the probability that a randomly selected bill will have an amount greater than $155, which the city believes might indicate that someone is wasting water. would a bill that size be considered unusual?

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