Chinese e-commerce giant Alibaba says its net profit for the three months ending December plunged 28 per cent to $US964 million ($A1.22 billion), hit by a one off charge and higher taxes. However sales soared 40 per cent to $US4.219 billion, and earnings per share were up 13 per cent to 81 US cents. Alibaba completed the world’s biggest IPO with its listing on the New York Stock Exchange in September. Headquartered in the eastern city of Hangzhou, Alibaba operates China’s most popula