I want to know the answer to the following question:
How many works of a cappella in musical theater have been successful in Off-Broadway productions?
All the background I'm provided with is that "A cappella has been used as the sole orchestration for original works of musical theater that have had commercial runs Off-Broadway (theaters in New York City with 99 to 500 seats) only four times.". Is that enough to answer the question?
Answer: yes