HELP please please! :D

Simplify 4 square root of 2 end root plus 7 square root of 2 end root minus 3 square root of 2 . (1 point) 2 square root of 8 8 square root of 2 8 square root of 6 6 square root of 8

Whats the name of the vertical axis

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