Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

Queen Elizabeth organised a royal party.

To Avoid uninvited guest royal family set a password.
Jack (an uninvited person) plan to enter the party. He stand nearby the door.

First guest comes, the security person said 'twelve' and guest replied with six.
Second guest comes , the security person said 'six' and guest replied with 'three'.

Jack thought is enough and he walked to the entry point. The security person said 'eight' , Jack replied smilingly 'four'.
He was immediately thrown out of the party. why ?

Can you count the number of squares in the figure below?

A bomb goes off.
Carnage.
One person, only a few feet away, survives! How can this be?

Can you solve the below geography rebus by decoding the below rebus ?

P is the father of Q and S is the son of R. T is the brother of P and has a daughter U. If R is the sister of P, then what is the relation between U, Q and S?

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

I go up and I go down.
I go up towards the beautiful sky and down toward the green ground.
I am present tense.
I am past tense too
Children love me.

Who Am I?

What makes this number unique: 8,549,176,320?