U.S. stock indexes opened sharply lower Tuesday after a three-day break, in observance of Martin Luther King Jr., with the high-growth technology sector trading sharply lower at the the start of a busy week of corporate earnings report. Meanwhile, a blockbuster tech deal was also in the spotlight, after Microsoft Corp. said it had reached an agreement to acquire Activision Blizzard Inc. in an all-cash deal valued at $68.7 billion. The Dow was down 529 points, or 1.5%, at 35,393, the S&P 500 index was off 1.3% at 4,600, while the Nasdaq Composite Index was off 1.7% at 14,651. The moves for stocks come as the 10-year Treasury note yields above 1.8% and the 2-year Treasury note breaches 1%.

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