美國九秒剷雪哥，影片一ＰＯ上網連舞王都甘拜下風！！太強惹～ 


美國一名網友日前在推特上傳了一段影片，從中可見一名身穿黑衣、頭戴紅帽的「鏟雪哥」，

在推著大雪鏟前進時不小心打滑，但他在四肢並用，

在冰上掙扎了9秒后，竟然若無其事地．．．太好笑了ＸＤＤ


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A curious connection : What's the function $f(x)$?

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Issue with $int_0^inftyfraccos(x^2)x^2dx$

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Equality of field extensions given Splitting field is $S_n$.

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