Can you replace the question mark with the correct letter?

6 + 6 + 6 = N
7 + 7 + 7 = E
8 + 8 + 8 = R
0 + 0 + 0 = ?

You know three triplets: Frank John and Wayne (need to return your money). Frank always tells the truth while John and Wayne always lie. You meet one of them on the road and can ask him a three-word question.
Which question, will you ask?

Spelt forwards I’m what you do every day, spelled backwards I’m something you hate. What am I?

Why did the Girl throw the butter out of the window?

The richest man in the city Mr Rechard is kidnapped. James Bond is appointed to the case. At the crime scene, a note is found written by Mr Richard. The note read:

"First of January, Fourth of October, Fifth of March, Third of June."

James Bond knew that somehow, the killer's name was hidden in the note. The following were the suspects:

Jack Richard, the son and the heir of property.
John Jacobson, the employee of Richard.
June Richard, the wife of Richard.

James Bond took only a few moments to deduce the killer's name. Can you tell who was the killer?

How can you spell "White of an egg" in one word?
Hint: I know you can spell coke, poke, and joke.

Find the smallest sentence with all the English alphabet.

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

If we add four times the age of John four years from now to five times his age five years from now we get ten times his current age.

How old will John be two years from now?

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