So now that means if this is where the center of positive excess charge lies and on top of it is the center there is no displacement of the charge so there is no net dipole.

所以现在我们说,如果正电荷中心,就位于,那么还是在这里负电荷中心也在这里,所以没有空间偶极。

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Third, although the top schools charge similar fees, outside that bracket there is a wide range to choose from.

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Executives need to see how social fits in to the overall vision and goals of the organization in order to lead a top down charge that changes how employees and customers connect and collaborate.

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Some cite the example of Chile, where a universal voucher scheme that allows schools to charge top-up fees seems to have improved the education of the best-off most.

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