the right answer is:
"Virus"
The sixth Kingdom Keepers book by Ridley Pearson, Dark Passage, will be out in April 2013.
no idea
I guess the "sixth kingdom" would refer to archibacteria. The reason these are often placed into a separate kingdom is because they have considerable differences from the living beings in any of the other kingdoms.
April 2013
Sixth = 6th
The name of the sixth book is In Too Deep
The United Kingdom is a First World country with an industrialized economy. It is the sixth largest economy in the world.
Kingdom Hearts Birth by Sleep is the sixth game released in the series, but chronologically takes place ten years before the first Kingdom Hearts.
the sixth book is called Fang, I think.
Saturn
George VI was 40 when he became King of the United Kingdom in 1936.
Avenue of the Americas is the legal name of Sixth Avenue in Manhattan. Locals still call it Sixth Avenue.