A hotel receives 60 visitors, of which 37 stay at least 1 week, 43 spend at least $30,000 daily, 32 are completely satisfied with the service; 30 stayed at least one week and spent at least $30,000 per day, 26 stayed at least one week and were fully satisfied, 27 spent at least $30,000 per day and were fully satisfied, and 24 stayed at least one week, spent at least $30,000 a day and were completely satisfied. 

a) How many visitors stayed for at least a week, spent at least $30,000 a day, but were not completely satisfied? 

b) How many visitors were completely satisfied, but stayed less than a week and spent less than $30,000 per day?