Twitter said Monday it has agreed to sell itself to Elon Musk in a roughly $44 billion deal that has the potential to expand the billionaire's business empire and put the world's richest man in charge of one of the world's most influential social networks. The deal, which will take the company private, caps off a whirlwind period in which the Tesla and SpaceX CEO became one of Twitter's largest shareholders, was offered and turned down a seat on its board and bid to buy the company — all in less than a month. Under the terms of the deal,