A traffic light at a certain intersection is green 55% of the time, yellow 10% of the time, and red 35% of the time. A car approaches this intersection once each day. Let Y denote the number of days up to and including the third day on which a red light is encountered. Assume that each day represents an independent trial.

Find P(Y=7)
Find the mean of Y
Find the Variance of Y

Three students, javier, sam, and corrine, participated in a fundraiser where people donated a certain amount of money per lap that the student ran. each student also had some initial donations that were collected before the run. the equations that represent each student's total donation, y, based on the number of laps ran, x, is shown below. match each equation with the correct rate of change for that student.