• There are many economic activities—
(i) primary
(ii) secondary
(iii) tertiary
(iv) quaternary
• They revolve around obtaining and utilising resources necessary for survival.
• (i) Secondary activities add value to natural resources by transforming raw materials into valuable products.
(ii) Cotton in the boll has limited use but after it is transformed into yam becomes more valuable and can be used for making clothes.
(iii) Iron ore after being converted into steel it gets its value and can be used for making many valuable machines, tools etc.
