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New Tab X + 391778 A survey was conducted where people were asked whether they have a preference for cats, dogs, birds, or no preference. The subjects may have preferred more than one animal. The Venn diagram below summarizes the results of the survey, and the values shown in the diagram are the number of people in each subset. Cats Dogs 15 13 4 Birds a. How many people preferred cats, but not dogs? b. How many people preferred both birds and dogs, but not cats? c. How many total people preferred cats? d. How many total people were surveyed? Remember to include those that chose no preference