How do you find the missing height of a trapezoid

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

For each proportion find the unknown number x 1/5/8=×/15

Atriangle has vertices of (0,3.5), (3,1.5), (0, -1.5). if it is dilated with center at the origin, and a scale factor of 2, what will be the coordinates of the image?