Questions

The alphabet 'Y' resembles same as the questioning word WHY in sounding.

Hence,  alphabet Y is a question.

Answer:  U

Explanation:  Start with the D on the outer left of the diagram, and move clockwise around the outer segments, then start on the N anti-clockwise around the inner segments. Letters advance through the alphabet in steps of 3, then 4, 5, and 6, repeating this sequence.

Most organic compounds contain carbon and hydrogen.

The amount of money you’ll get for a given amount of your country’s currency is based on internationally determined exchange rates. Exchange rates can be either fixed or floating. Fixed exchange rates use a standard, such as gold or another precious metal, and each unit of currency corresponds to a fixed quantity of that standard that should (theoretically) exist.

Silver is the best conductor of both heat and electricity among metals with a thermal conduction value of about 430 W/(mK).

Gold and copper both come respectably close to silver.

Copper being significantly less costly it is often chosen over silver in many applications.

We know that, 

Earth is known as Watery planet.

Neptune is known as Blue planet. 

The first oil well was dug in 1859. The oil production has since declined but it retains its name for high grade oil

The ancient goal of astrology was to predict human events.