A group of 35 tourists can choose between visiting the Aero Space Museum of Calgary (A), the Calgary Zoo (Z), or the Glenbow Museum (G). . 18 went to the Aero Space Museum, 21 went to the zoo, and 23 went to the Glenbow Museum. . 2 went to both museums but not the zoo. . 3 went to the Aero Space Museum and the zoo only. . 6 went to the Glenbow Museum and the zoo only. 17. a. How many tourists went to all three attractions? Use a Venn diagram to help with your answer. (3 marks) b. Using set notation, provide one way to identify the shaded region. (1 mark)