Which is the rope you never skip with?

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?

I am a word of 12 alphabets.

* Alphabets 12, 4, 7, 2, 5 : Eastern beast of burden
* Alphabets 1, 8, 10, 9 are street made famous by Sinclair Lewis.
* Alphabets 11, 3, 6 are past.

On whole it means a person suffering from delusions of greatness.

What Is it ?

John can fit six large chocolate boxes or nine small chocolate boxes into a carton. How many cartons will he require to put sixty-six chocolate boxes into?

What number comes next in this sequence:
7 8 5 5 3 4 4 _

A man was gazing through the window of the 23rd floor of the building. He suddenly opened the window and jumped on the other side of the window. On landing on the floor, there was not a sheer mark of injury on him.

How can that be possible if he did not use any kind of parachute and did not land on a soft surface?

Find the next number in the series.
1 10 24 43 67 ?

In a box, there is a jumble of 7 red balls, 6 blue balls, 5 green balls, and 4 yellow balls. What is the minimum number of balls, will you have to pick up so that you have at least 4 balls of the same colour?

You board a train. The train will have to enter a tunnel soon. You are claustrophobic. Which place is the best for you to sit?

How many letters are in the alphabet?