Heather: us stocks taking a big hit thursday as investors react to apple's business forecasts. tracy carrasco here with more on why apple sent shockwaves across the globe. >> reporter: apple leaving investors with a sour taste yesterday. america's first trillion dollar company thoughts worst day and 60 is wiping away $70 billion in market value. shares of the company plummeting 10% every warning from tim cook that iphone sales are suffering because of china's worsening economy. that sparked new fears of the global economic slowdown sending without thinking 660 points, the nasdaq down 3%, the s...