Mr.Obama spoke in advance of meeting at the U.N. late Wednesday of foreign ministers of the five permanent U.N.Security Council member countries and Germany - the P5+1, who have been trying to re-engage Iran in negotiations on its nuclear program.

VOA: standard.2009.09.23

Again we have the charge of the nucleus on plus 2, +2 but let's say this time the electron now is going to be very, very close to the nucleus.

对于我们的氦原子，我们有一次得到了原子核电荷量为,但是我们说这次电子。

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