U.S. stocks were higher, with the Nasdaq Composite gaining more than 100 points on Monday.Shares of Tesla, Inc. TSLA rose sharply during Monday's session after CEO Elon Musk purchased massive number of shares, according to a recent regulatory filing.Musk, through the Elon Musk Revocable Trust, bought 2.57 million shares of Tesla on Friday, September 12. The shares were acquired at prices ranging from approximately $371 to$396 per share, as per a Form 4 filing with the Securities and Exchange Commission (SE ...