Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

I am an odd number. Take away a letter and I become even. What number am I?

I have nine bottles of wine and one of the nine bottles is poisoned.
I need to find the poisoned bottle with two facts
(1) Poison is deadly, only a sip will cost death
(2) I have two mice to do so.

How should I do it?

Why do we preferably have round manhole covers and not square ones?

What am I?

Rearrange the letters in "new door" to make one word.

I start and end with 500 and carry a 5 in my heart. But I require the first letter and the first number to be complete. I am the name of a King.

Who am I ?

Why blonde cannot dial 911?

Christina is older than Kareena and Karishma. Katrina is older than Karishma and younger than Kareena. If Kareena has a brother named John, who is older than Christina, who's the youngest?