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      Li Lei has a good friend.    1    name is Jim. He is   2     the USA. He likes   3    food very much. He can    4    English and   5    Chinese. Li Lei and Jim are in the same(相同的)   6   . They are classmates(同学). They go to school five    7    a week. They stay    8   home on Saturdays and Sundays. At school they play    9    after class. They like swimming,    10   .

将分式方程 $1-\frac{2x}{x-1}=\frac{3}{x-1}$ 去分母,得到正确的整式方程是(     )

将经处理后的胚胎干细胞，移植到因胰岛受损而患糖尿病的小白鼠体内后 ，该鼠血糖浓度趋于正常。上述事实说明（   ）

已知数列{a_n}中，a_n+1=3S_n，则下列关于{a_n}的说法正确的是（　　）