A group of 125 students completed a questionnaire. The following data were collected: • 77 students had a Visa card; • 64 students had an American Express card; • 30 students had a Discovery card; • 35 students had a Visa card and an American Express card, but not a Discovery card; • 12 students had a Visa card and a Discovery card, but not an American Express card; • 7 students had an American Express card and a discovery card, but not a Visa card: . 4 students had all three cards. a) Represent this information in a Venn diagram. b) Calculate the number of students who own none of the cards mentioned above. c) How many students own only a Visa card? d) How many students own both a Visa card and a discovery card? e) How many students own at least two of the cards?