Geographic Trivia: What Asian country has the highest population density?

Questions

China has the largest Buddhist population (107,000,000). Name the country having either the 2nd or 3rd largest Buddhist population?

Israel has a Jewish population of 4.8 million people. Which country has more?

Nepal has a Hindu population of 21.3 million. Which country has more, at 824 million?

This country has the world's largest Muslim population, at over 182.5 million people?

At 21 square kms, this is the world's Smallest island country?