Question 5. Consider a family with a mother, father, and two children. Consider the following set of events: A1 = {mother has influenza} A2 = {father has influenza} A3 = {first child has influenza} A4 = {second child has influenza} B = {at least one child has influenza} C = {at least one parent has influenza} D = {at least one family member has influenza} a. Question #14 What does A1 A2 mean? b. Question #15 Are A3 and A4 mutually exclusive events? c. Question #16 Express D in terms of B and C.