How many Facebook users in the world NOW?

How many Facebook users in the world NOW? how many communist country in the world? How many nations in the world How many continents are there in the world?翻译 How many letters are there in the world?脑筋急转弯 how many letters are there in the "world". how many letters are there in the "world" __________are widely used in the modern world.How many d____ How many _____ died in the Second World war? ( fight ) How many nations are there in the world? How many l______languages are there in the world? How many letters are there in the world?-----____________.(回