I want to know the answer to the following question:
How many carriers did Nagumo have at the Battle of Midway?
All the background I'm provided with is that "Alerted to the need of a second strike on Midway, but also wary of the need to deal with the American carriers that he now knew were in the vicinity, Nagumo twice changed the arming orders for his aircraft.". Is that enough to answer the question?