A new dam being built has the shape of a trapezoid. The length of the base at the bottom of the dam is 2 times the height.
The length of the base at the top of the dam is times the height
minus 30 feet.
5
a. Write an expression to find the area of the trapezoidal cross
section of the dam.
b. If the height of the dam is 180 feet, find the area
of this cross section.

Find the number of positive three-digit even integers whose digits are among 9, 8, 7,5, 3, and 1.

How many credit hours will a student have to take for the two tuition costs to be equal? round the answer to the nearest tenth of an hour.

Four airplanes carrying a total of 400 passengersarrive at the detroit airport. the airplanes carry, respectively,50, 80, 110, and 160 passengers.a) one of the 400 passengers is selected uniformly at random.let x denote the number of passengers that were on theairplane carrying the randomly selected passenger. find var(x)for x as given in the problemb) one of the 4 airplane drivers is also selected uniformly atrandom. let y denote the number of passengers on the chosen driver’s airplane. find var(y) for y as given in the problem