Which describes an investment in which all of the money to be invested is deposited at one time

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

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Consider the following equation. 1/2x^3+x-7=-3sqrtx-1 approximate the solution to the equation using three iterations of successive approximation. use the graph below as a starting point. a. b. c. d.