Debra tutors history. For each hour that she tutors, she earns 50 dollars. Let E be her earnings (in dollars) after tutoring for H hours.

Write an equation relating E to H . Then use this equation to find Debra's earnings after tutoring for 19 hours.

Express the following as a function of a single angle, cos(60) cos(-20) - sin(60) sin(-20)

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 coefficient matrix represents a system of linear equations that has a unique solution ? options in photo*