Most Populated Countries Containing 'U'

How many of the world's 24 most populous countries can you name?

Can you name the countries of the world where at least 50% of residents are Islamic?

Can you name the 26 nations that have at least one urban area with 10,000,000 or more inhabitants? The '#' column is the number of megacities.

Name the countries that added the most people in each decade since the 1950s.