2013- 10- 2
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#152
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متميزة بملتقى الطلاب والطالبات الترفيهي
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رد: The 3rd day of the English competition
Heavy water, formally called deuterium oxide or 2
H
2
O or D2O, is a form of water that contains a larger than normal amount of the hydrogen isotope deuterium,
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