从总体中抽取样本容量为5的样本，若样本观测值是5，6，6，3，10，以下哪个说法正确?
A. 样本方差S2=5.2
B. 样本二阶中心矩B2=41.2
C. 样本二阶中心矩B2=26/5
D. 样本二阶中心矩B2=6.5
（obvious ), he is the most excellent student in the whole class
This gun is designed for one purpose—it's(basic) to kill people.
He was finding it(increase) difficult to make decisions.
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