There is one four-digit whole number n, such that the last four digits of n2 are the original number n

A crime was committed at baker street. Ibrahim Dakota who was shot in the stomach was the main suspect. Sherlock questioned the suspect. The conversation started as:
Sherlock: What's your story, Ibrahim?
Ibrahim: I was walking around baker street and suddenly a man from the back shot me. I ran as fast as I could to save my life".
Sherlock: That is enough (and ask the police to arrest him).

Why does Sherlock think he is the murderer?

Find the missing value of "?" in the letter sequence below.

CAD
EBG
KBM
OCR
DDH
NL?

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

I have one of the three numbers: 1, 2, or 3 in my mind. I speak only truth. You can ask me just one question for which I will only reply in yes or no or don't know. What question will you ask from me so that you are able to know the number?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

A seven-year-old kid challenged his classmates that he can make the number one disappear by adding something to it.

How can he do that?

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

A Child was born in Lahore, Pakistan. Still, the child is not a Pakistani citizen. why?

Solve the riddle below:

If a Chicken says, 'All chickens are liars" is the chicken telling the truth?