There are 56 students in travel club. they discovered that 21 memebers have visited country A, 25 have visited country B, 26 have been to country C, 9 have visited countries A and B, 14 have been only to country C, and 11 have been only to country A. some club memebers have not been to any of the three foreign countries, and, curiously, an equal number have been to all three countries

A. how many students have been to all three countries ?

B. how many students have been only to country b?