What do you understand by camel caravan? Brief description.​

A camel train or caravan is a series of camels carrying passengers and goods on a regular or semi-regular service between points. ... Camel trains were also used sparingly elsewhere around the globe. Since the early 20th century they have been largely replaced by motorized vehicles or air traffic.

20: 5

explanation:

about 20% of the world's population lives in   southwest asia, but on less than 5% of the world's   land area.