Which one of the following is the North Dravidian

Device used to convert sound into electrical signals:

Which gas is commonly used in electric bulbs to prevent oxidation?

Which of the following element is required for the conversion of the solar energy? 

With increase in impurities, the boiling point of water _________?

Which vitamin is also known as Vitamin-B2?

The gap between two neurons is called a 

Which of the following materials has the highest thermal conductivity?

Which of the following is a plant hormone?

Respiration in the absence of air is called

Zero group was introduced by