Outspoken Elon Musk has doubled down on his new work-from-home ultimatum sent to Tesla staff Tuesday, sending out a second email to say 'if you don’t show up, we will assume you have resigned.' 'Everyone at Tesla is required to spend a minimum of 40 hours in the office per week,' Musk, 50, wrote in a second email sent to staff just hours after the first, which was leaked and reported by Teslarati. The message, shared by Twitter user @SamNissim, bears the subject line 'To be super clear' and was sent to an email list labeled 'Everyone' at 10:51 pm....