Michael returned to Silicon Valley where, following a brief run at social media analytics company Klout, he joined Uber in 2013 as chief business officer and a close lieutenant to CEO Travis Kalanick. Over the next four years, he helped orchestrate one of the most aggressive expansions in corporate history, in which Uber raised nearly $15 billion and saw its valuation soar to roughly $70 billion.
3月24日，北京市少年宫，学生科技节优秀获奖作品展上，北京市育英学校的学生在展示校园环境智能导览系统。新京报记者 李木易 摄
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'Definitely busier'
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