What is the fastest way to double your money?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

It is a nine-letter word.
The exact opposite of the phrase "friendly and outgoing"
It contains the word "over".
It starts will a vowel.

What is it?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

John asked Jack, "The time right now is 7 pm. Can you tell me what will be the time 23, 999, 995 hours later ?"

While Bella does not know the answer, do you ?

What goes up but never comes down?

If eleven plus two equals one, what does nine plus five equal?

There are nine letters in the below-given diagram. You have to form a nine-letter word using these letters.

A man has eighty-one cows ( numbered 1,2,3...81 as such). The beauty is that cow no. 1 gives 1ltr of milk, cow no. 2 gives 2ltrs of milk and so on. The man wants to equally distribute the cows among his nine sons so that each one of them gets the same quantity of milk.