A device, which is used in our TV set, computer, radio set for storing the electric charge, is

What do plants, which grow in salt-rich soils, say?

The best conductor of heat among the following is

The 'Greenhouse effect' is produced due to the presence of excess amount of  

Transportation of food in plants takes place through:

In the following is not an example of refraction of light.

The metal used to recover copper from a solution of copper sulphate is

Which of the following is usually not an air - pollutant?