There are 500 500500 students in a high school senior class. Of these 500 500500 students, 300 300300 regularly wear a necklace to school, 200 200200 regularly wear a ring, and 125 125125 regularly wear a necklace and a ring. Using this information, answer each of the following questions. Let N NN be the event that a randomly selected senior regularly wears a necklace and R RR be the event that a randomly selected senior regularly wears a ring.