Select the correct answer. Which expression is equivalent to the given polynomial expression? (-4a2 – 3b) + (-2ab -a2 +b2) + (-b2+ 6ab)

OA.-3a2 +2b2 + 8ab + 3b
OB.-3a2 + 4ab + 3b
O c. -5a2 + 4ab - 3b
D.-5a2 + 2b2 + 8ab + 3b

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

Graph y ≥ -x^2 - 1. click on the graph until the correct graph appears.

Estimate the area under the curve f(x) = 16 - x^2 from x = 0 to x = 3 by using three inscribed (under the curve) rectangles. answer to the nearest integer.