Can you convert the number zero(0) into a positive number using just one mathematical operator ?

Two Twins Jack and Jill were standing back to back and suddenly they started running in opposite direction for 4 kilometres and then turn to left and run for another 3 kilometres.

what is the distance between the Baggio twins when they stop ?

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

With the help clues provided in the image, can you find the 5 digit key?

What is black when you buy it, red when you use it, and gray when you throw it away?

A girl was sitting in her hotel room when she heard a knock on the door. She opened the door and found that a man was standing outside.
The man said, "Oh! I am really sorry, I thought this was my room."
He then walked through the corridor to the elevator. The girl did not know the man. She closed her door and called security asking them to apprehend the man.
What made her suspicious of that man? He might have been genuinely mistaken.

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

As a whole I am both
safe and secure.

Behead me and I become
a place of meeting.

Behead me again and I am
the partner of ready.

Restore me, and I become
the domain of beasts.

What am I?

Two in a corner, one in a room, zero in a house, but one in a shelter. What am I?

Can you count the number of quadrilaterals in the picture below?