The graph shown here displays the distance, in miles, traveled by an airplane in a certain number of hours. based on the graph, which of the following equations indicates the correct variables, and in how many hours does the airplane travel 8,000 miles if it travels at the same speed? a. x = 200y, the airplane travels 8,000 miles in 42 hours b. y = 200x, the airplane travels 8,000 miles in 42 hours c. x = 200y, the airplane travels 8,000 miles in 40 hours d. y = 200x, the airplane travels 8,000 miles in 40 hours