Find the horizontal and vertical line

How do i do this? i don’t understand

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

Jaxon has s packs of 8 crazy straws. he divided the crazy straws into 2 equal bags. now, he has 224 crazy straws in each bag. how many packs of crazy straws did jaxon start with?