Find a · b. |a| = 60, |b| = 90, the angle between a and b is 3π/4.

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Which expression gives you the distance between the points (5,1)and(9,-6)

Monitors manufactured by tsi electronics have life spans that have a normal distribution with a standard deviation of 1800 hours and a mean life span of 20,000 hours. if a monitor is selected at random, find the probability that the life span of the monitor will be more than 17,659 hours. round your answer to four decimal places.