How to answer Elon Musks favorite job interview question

SpaceX CEO Elon Musk likes to ask one riddle in particular when interviewing candidates for a position with his company, according to the book Elon Musk: .
Interviewing with Elon Musk is not for the faint of heart. Musk, the chief executive of Tesla and SpaceX, is known to appear disinterested in candidates at first .
The engineer-magnate is a co-founder of electric-car maker Tesla Motors. Elon Musk will now take your questions.
At the International Astronautical Congress, SpaceX CEO Elon Musk unveiled his ambitious plans for interplanetary travel. Afterwords he fielded some very .