Why is the Hole below a Lock?

The peacock is a bird that does not lay eggs. How do they get baby peacocks?

In a university, a professor gave a set of three problems to the three brilliant students of his class. See the image for the questions.

Using four sevens (7) and a one (1) create the number 100. Except for the five numerals, you can use the usual mathematical operations (+, -, x, :), root and brackets ()

When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

I am white when I am dirty, and black when I am clean. What am I?

There is a movie name hidden in the picture that is attached with this question. Can you find out which movie is it?

In the picture given below, can you find out which digit will take place of the question mark?

Things are just as they seem, right? Well, check again.
Can you count the number of tigers in this picture ?

I come in different shapes and sizes.
Parts of me are curved, other parts are straight.
You can put me anywhere you like,
but there is only one right place for me.
What am I?