Explain why in paper-and-pencil addition and subtraction the terms trading and regrouping are used instead of the terms carrying and borrowing

Identify whether the figure has plane symmetry, symmetry about an axis, or neither.

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

Reinel saves 30% of every pay check. his paycheck last week was 560$. how much did reniel save last week?