Elon Musk’s Monster Week of Juggling Twitter, Tesla and SpaceX

Even by the standards of Elon Musk, the world’s richest man and serial entrepreneur, this week was one for the ages.

Tesla stock, which underpins the billionaire’s wealth, had one of its worst weeks after the auto maker’s delivery figures fell short of Wall Street expectations. His rocket company ferried astronauts to the International Space Station, and his business empire appeared to be on the cusp of expanding to include one of the best known social-media networks.