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?

What does the below image rebus riddle means ?

What am I?

Complete the series by replacing "?" with the correct number.

ST ND RD TH '?'

A woman lives in a Tall building thirty-six floors high and served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

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

A detective visits his friend John just to discover that John's neighbour Dr Jacob was murdered. Dr Jacob, who is a mathematician wrote the murderer's name in a code word "Hcqtfz". There were five suspects
1. Ajit
2. Pankaj
3. Ganpat
4. Deenu
5. Hariya

The Detective was instantly able to find the murderer.
Can you?

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

I noticed one of the words in the oxford dictionary is spelled incorrectly. What about you?

There are seven sisters in a house in a village where there is no electricity or any gadget.

Sister-1: Reading Novel
Sister-2: Cooking
Sister-3: Playing Chess
Sister-4: Playing Sudoku
Sister-5: Washing clothes
Sister-6: Gardening

what is Sister-7 doing ?