Find the coefficient of the x7y2term in the binomial expansion of (x+y)^9

Aladder that is 30 ft long needs to reach 27 ft up a building. what should the angle of the vertical be?

Monthly water bills for a city have a mean of $108.43 and a standard deviation of $36.98. find the probability that a randomly selected bill will have an amount greater than $173, which the city believes might indicate that someone is wasting water. would a bill that size be considered unusual?

Find the sixth term of the following geometric sequence.