Market mayhem, a sector pulse check and Apple gone rotten?

The red-hot tech sector is cooling off, leading today’s sharp move lower for the averages. Our experts break down why there’s a sudden change in market confidence. Plus, amid today’s rollercoaster market action, we drill down on what’s happening for Tesla, leisure stocks and the restaurant sector. And, Apple is one of the biggest drags on the Dow, on pace for its worst day since mid-March. Is this simply investor profit-taking after completing its stock split, or a sign of trouble ahead? We debate.