Question: The Ravello Festival is also popularly known as the "Wagner Festival" and is an annual summer festival of music and the arts, the composer had been so taken with the beauty of the Villa Rufolo in Ravello that he is said to have proclaimed, in reference to a character in his own opera Parsifal, an opera in how many acts by the German composer?
Sentence (from "Opera Saratoga"): It performs an annual summer festival of three fully staged operas and operettas.
Relevant evidence: No