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 = ?

John and Jacob are twin brothers. One of them is a liar whereas the other one is a truth-teller.

I called their home number and one of them picked up.
I asked. 'Does John lie?' The person replied with a yes.

Whom did I talk with, John or Jacob?

There is a straight highway. Four different villages lie on that highway. The distance between them is different. The third village is 60km away from the first village; the fourth is 40 km away from the second; the third is 10 km near to the fourth that it is to the second.

Can you calculate the distance between the fourth and the first village ?

Can you find a number that lies one third of the distance between 1/3 and 2/3?

Count the number of lines in the image below ?

Can you decipher the following common phrase?

T M C
A U O
H S M
W T E

Can you find the mistake in the below statement?

What is the longest word in the dictionary?

What has many teeth, but cannot bite?

Find the value of "?" in the ball picture Riddle below: