When did the ipad 1st gen come out?
No context provided
When did the ipad 1st gen come out in United States as Wi-Fi variant?
April 3, 2010
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When did the ipad 1st gen come out in United States as "Wi-Fi + Cellular" variant?
April 30,2010
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When did the ipad 1st gen come out in Spain,Italy,Switzerland,United Kingdom,Germany,Australia,Japan,Canada,France?
May 28, 2010
No context provided
When did the ipad 1st gen come out in Austria,Belgium,Hong Kong,Ireland,Luxembourg,Mexico,Netherlands,New Zealand,Singapore?
July 23, 2010
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When did the ipad 1st gen come out in China?
September 17, 2010
iPad (1st generation)
https://en.wikipedia.org/wiki/iPad%20%281st%20generation%29
The first-generation iPad (/ˈaɪpæd/ EYE-pad) is a tablet computer designed and marketed by Apple Inc. as the first device in the iPad lineup of tablet computers. 
IPad (1st generation)
The first-generation iPad is a tablet computer designed and marketed by Apple Inc. as the first device in the iPad lineup of tablet computers. It had multiple versions released between April and September of 2010. On April 3, 2010, the Wi-Fi variant was released in the United States, and on April 30 they released the same version with cellular. On May 28, 2010, it was released in Spain, Italy, Switzerland, UK, Germany, Australia, Japan, Canada, and France. On July 23, 2010, it was released in Austria, Belgium, Hong Kong, Ireland, Luxembourg, Mexico, Netherlands, New Zealand, and Singapore. Finally, on September 17, 2010, it was made available to people in China.