ПОМОГИТЕ ОТВЕТИТЬ НА ВОПРОС !!!

[email protected] в категроии Английский язык, вопрос открыт 19.09.2017 в 09:20

Why does the atmosphere in some cities with clean air become worse in winter?

However, the atmosphere in some cities with clean air gets worse in winter. Helsinki, for example, becomes one of the cities with the largest proportion of S02 in the air in winter. This must be connected with the heating of houses.