A survey of 93 college students was taken to determine the musical styles they liked. Of those, 36 students listened to rock, 34 to classical, and 43 to jazz. Also, 23 students listened to rock and jazz, 15 to rock and classical, and 22 to classical and jazz. Finally, 13 students listened to all three musical styles. Construct a Venn diagram and determine the cardinality for each region. How many students listened to classical and jazz, but not rock?