John named his first son Alpha, second Beta, third Charlie and fourth Delta. What is the fifth son's name?

Intelligence Agency need to break the vault but the problem is that they are not able to break the vault.

On the vault, a text is written as:

31 11 33 33 43 45
21 25
31 24 11 31 51 41

To Break the code Intelligence Agency brings a mathematician named Joseph.
Minutes later he deciphers the code.

Whats the code?

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

You can take four of the five letters out of this word, but the pronunciation never changes. What is the word?

A mathematician couple was having a Frappuccino in Starbucks sitting opposite to each other. Suddenly the guy noticed the text written on the paper in front of them and exclaimed that it was wrong. The girl denied it and said it is appropriate. Both are correct. What is written on the paper?

Replace the question mark in the picture below.

Complete the series by replacing "?" with the correct number.

ST ND RD TH '?'

When I get multiplied by any number, the sum of the figures in the product is always me. What am I?

A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?

In a concert, Christina is performing a dance show with her group.
At 10:00, she and her crew were dancing in an absolutely straight line. At that time Christina was standing in 4th position from both the front and back end of the row.

What was the size of her crew?