Help!! Please help find the surface area of this cone and answer the questions below. :(

Is δ pmr similar to δ smn ? if so, which postulate or theorem proves these two triangles are similar?

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

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?