Part 2. In a market research survey 215 persons were asked if they during the last year had used any of three competing products A, B and C. 96 person have used A, and of these 42 had used A only. 89 persons have used B, and of these 10 had used B only. 137 persons have used C, and of these 39 had used C only. 62 persons have used B and C. a) Are there any person who has used all three products A, B and C? b) How many persons didn't use any of the products A, B och C? c) How many persons have used product B or C? Always, do your calculations and give your answer using \"exact numbers", do not round off (no approximate values). For example, if the answer is x 2 J5 , you give the answer like that