[单选题]下列说正确的是

正确答案 ：D

元素周期律是元素原子核外电子排布周期性变化的结果

[单选题]--My mother is preparing my favorite dishes, Go with me and have a taste, okay?--_______. And I’ll be glad to meet your parents.

正确答案 ：A

I think so

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