I can write cow in 13 letters.

Can You?

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?

Move three sticks of the spiral below to form a square.

Outside a tattoo artist's shop, there was a signboard which read 'I make tattoos on only them who do not tattoo themselves'.

Reading it what do you think, does the tattoo artist tattoo himself?

If Rajina's daughter is my daughter's mom, who am I to Rajina?

If Bihan is 10, Anirudha is 20, and Kim and Seal are both 5, but Rikold is 10, how much is Kenniger by the same trend?

What are the 50th, 63rd and 100th numbers in the sequence below?
4, 5, 8, 8, 9, 9, 12, 13, 13, 13, 17, 18, ...

Assume there are approximately 5,000,000,000 (5 billion) people on Earth. What would you estimate to be the result, if you multiply together the number of fingers on every person's left hand? (For the purposes of this exercise, thumbs count as fingers, for five fingers per hand.) If you cannot estimate the number then try to guess how long the number would be.

It is always ahead of me yet I can never see it. What is it?

I was speeding and ran through a stop sign, yet two traffic officers who were there do nothing about it.

why?