Shares of AOL Inc. shot up 19% in premarket trade Tuesday, after the Internet content company agreed to be acquired by Verizon Communications Inc. in a deal valued at $4.4 billion. Under terms of the deal, which will take the form of a tender offer that is followed by a merger, Verizon will pay $50 for each AOL share, which represents a 17% premium to Monday's closing price. The deal is expected to close in the summer. Verizon said it expects to fund the purchase with cash on hand and commercial paper.