What is the fastest way to double your money?

What number should come in place of the question mark below?

If six children and two dogs were under an umbrella, how come none of them got wet?

In the Wild West, you are challenged into a death match by two bounty hunters nicknamed Golden Revolver (GR) and Killer Boots (KB). You accept the challenge. None of you want to waste any of the bullet and so a certain rules are laid down:

1) All of you will shoot in a given order till the last man standing.
2) Each of you shoots only once upon his turn.
3) If any one of you is injured, the other two will finish him off with an iron rod.
4) The worst shooter of all (which is you) shoots first and the best one shoots at the last.

Now, how will you plan things if you know that you hit every third shot of yours, KB hits every second shot and GR hits every shot ?

Before Mount Everest was discovered, what was the highest mountain in the world?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

What goes up but never comes down?

What will you call your mother's brother's brother-in-law?

Which country gets ill every time?

Let's play a word game. Following are some meaningless words that can be completed by adding random letters on either side of the word.

For example, the word "rdo" can be formed into "pardon".

Using the same technique, can you complete the given words?
ecalc
airb
rinci
tibac
uidel
gorit
igna
eyho