Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

How many words can a quill made with the feather of a pigeon write with a 100ml bottle of black ink?

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

John was working on a Chemical Mixture whose weight comprise 90% liquid and 10% solid. The total weight of the mixture is 20 pounds. After a while, John noticed that some of the liquid evaporated and now the liquid comprises just 50% of the weight.

What is the weight of the chemical mixture now?

You can see it everyday, But cannot touch it at will. What is it?

What's a single-digit number with no value?

In the image below, can you find the value of an angle(y)

Using eight eights and addition only, can you make 1000?

As we know that white starts the game of chess. Can you find the scenario shown in the picture below is possible when all the white pieces are at the original place while the black pawn is not as in the below picture?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?