Here "himself" emphasizes that Jesus was alone in the stern. Alternate translation: "Jesus himself was alone" (See: [[rc://en/ta/man/jit/figs-rpronouns]])
The disciples asked this question to convey their fear. This question can be written as a statement. Alternate translation: "you need to pay attention to what is happening; we are all about to die!" (See: [[rc://en/ta/man/jit/figs-rquestion]])