You are standing outside the school, waiting to cross the street, when you hear booming music coming from an approaching car.
Sketch a graph that shows the relationship between how far away from you the car is and the loudness of the music.
Remember that the car is going by you, not at you. (The graph will not be a line.)
Which is the dependent variable and which is the independent variable?
Think about which depends on the other, the loudness or the distance.
The loudness is the dependent variable and the distance is the independent variable.