What do you answer even though it never asks you questions?

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?

Which is the rope you never skip with?

A blonde put eyeliner on her head. Why?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

What question can you never answer yes to?

What country can make you shiver?

What does below Rebus say?

XLR8

What has 13 hearts but no other organs?

There once were seven dwarfs who were all brothers. They were all born two years apart. The youngest dwarf is seven years old. How old is his oldest brother?