Прочитайте текст и определите, какой из заголовков соответствует тексту
The US economy consists of three main sectors - the primary, secondary, and tertiary.
Secondary economic activities involve processing or combining materials into new products, and include manufacturing and construction, this sector accounts for approximately 23 per cent of the gross national product (GNP).
Primary Economic Section of the USA
Tertiary Economic Section of the USA
The Gross National Product
Secondary Economic Section of the USA