Please show all your steps and explanations. Thank you!

7. Exponential Darts (10 points) You throw a dart at a circular target of radius "r. Let X be the distance of your dart's hit from the center of the target. You have improved and your aim is such that X N Exponential(4/'r). (Note that it is possible for the dart to completely miss the target.) (a) [6 Points] As a function of '1\