when did the 2nd generation ipad come out
March 2, 2011
IPad 2
 On March 2, 2011, CEO Steve Jobs unveiled the device at the Yerba Buena Center for the Arts, despite being on medical leave. Upon the announcement of the iPad 2, the original iPad was discontinued from sales online and at Apple authorized retail stores.
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IPad 2 [SEP] History
Apple sent invitations to journalists on February 23, 2011, for a media event on March 2. On March 2, 2011, CEO Steve Jobs unveiled the device at the Yerba Buena Center for the Arts, despite being on medical leave. Upon the announcement of the iPad 2, the original iPad was discontinued from sales online and at Apple authorized retail stores. Apple began selling the iPad 2 on its website on March 11, and in its U.S. retail stores at 5 pm local time on that date. Many stores in major cities, such as New York, sold out within hours. Online shipping delays had increased to three to four weeks on Sunday and four to five weeks by Tuesday.