Question: are the abba members in mamma mia 2?
Answer: 2. Two members of ABBA have bit-parts. Both Björn and Benny have cameos in 'Mamma Mia! ... Björn appears as an Oxford professor in the film's opening number, 'When I Kissed the Teacher', while Benny pops up as a piano player in a Paris café for 'Waterloo'.