task 7- match of topics

Topic	Index keyword
1-      Railways	Transportation
2-      Cultivation of oranges	Citrus farming
3-      Troposphere	Atmosphere
4-      Cotton growing	Industrial crops
5-      Under population	Population
6-      Panama canal	Sea routes
7-      Growth of  new York	Urbanisation
8-      Uranium	Ores
9-      Coal  production	Mining
10-   Rainfall	Climate