A single card is drawn at random from a standard 52-card deck. Let A be the event the card is red, B the event it is a face card, and C the event it is a spade. Given P(A)=21, P(B)=5212, P(C)=41, P(A∩B)=526, P(A∩C)=0, P(B∩C)=523, and P(A∩B∩C)=0, find the probability that exactly one of the events A,B,C occurs.