The night started our ordinarily enough. Jack and Tara，our 1 ，were in their small beds surrounded by toy animals. My husband，Pat，and I went to sleep 2 . 3 after midnight，Jack quie
As researchers learn more about how children’s intelligence develops, they are increasingly surprised by the power of parents. The power of the school has been replaced by the home. To begin with,
.因此x变化时,y′、y的变化情况如下表:
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,2)