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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

What is the effect on the graph of the function f(x)=x when f(x) is replaced with -f(x)+4

What is the slope of the line passing through the points (3, 3) and (5, 7) ? 1. 2 2. 1/2 3. −2 4. −1/2