Question

which areas have high density of population?Like river valleys etc....​

Answer 1

Answer:

valleys are very high populated

Answer 2

Answer:

Many of the world's small island or isolated states have large populations for their size. Macao, Monaco, Singapore, Hong Kong and Gibraltar are the five most densely populated. Singapore has nearly 8,000 people per km2 – more than 200 times as dense as the US, and 2000 times that of Australia.