Help a girl out please and thank you.

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

Which expression represents the total perimeter of her sandwich, and if x = 1.2, what is the approximate length of the crust?

Avideo game enthusiast saved $750 to spend on a video game player and games. the player costs $400. the games costs $49 each. at most how many games can this enthusiast buy along the player