Плотность раствора Na2CO3 равна 1102 кг/м3. из 4л этого раствора при дейтсвии соляной кислоты получено 66,6 л CO2 при 10*С и 100 кПа. вычислить  массовую долю (%)Na2CO3 в растворе.

Пожалуйста решите эту задачу!!!!!!!! В урне 6 пуль из которых 3 белые наугад вынуть две кули.Какая вероятность того, что они оба будут белыми.

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Some parents are wary about their children growing up. In particular, some fathers and mothers become alarmed and uncomfortable when their little girl starts dating. Many parents worry their daughter may become sexually involved and pregnant, which they believe will adversely affect her and interfere with their dreams and hopes for her having the good life. When teenagers assert their right to becoming more independent, it changes the components of the family system. Any change in the components of the system will create tension within the family. This tension is expressed by teens with such statements as " You dont understand me", " Get of my back", " I know what Im doing  dont treat me like a baby."

Al + HNO3 = Al(NO3)3 + NH4NO3 + H2O дописать уравнение ОВР и определить коэффициенты