An airplane reaches its cruising hight. at this height it travels at a constant speed, or rate and travels 2,000 mile in 4 hours. what is the rate of the plane? if the estimated cost per mile of the plane is $20, what is the cost of the 4 hour travel?

Dana wants to identify the favorite professional baseball team of people in her community. she stands outside a local sporting goods store and asks every other person who enters, "what is your favorite professional baseball team? " will the results of her survey be valid? explain.