If a worker produces 175 parts per hour, how many can be produced in 7 hour?

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 basic geometric term has no width, no length, and no thickness? line b. point c. angle d. plane

Does anyone know how to solve and graph this: 4 + | a + 2 | < 7the only part i don't get is the "4 +"