I want to know the answer to the following question:
What did former BYU graduate Harvey Fletcher invent?
All the background I'm provided with is that "BYU alumni in academia include former Dean of the Harvard Business School Kim B. Clark, two time world's most influential business thinker Clayton M. Christensen, Michael K. Young '73, current president of the University of Washington, Matthew S. Holland, current president of Utah Valley University, Stan L. Albrecht, current president of Utah State University, Teppo Felin, Professor at the University of Oxford, and Stephen D. Nadauld, previous president of Dixie State University.". Is that enough to answer the question?
Answer: no