The Liberty Tree was a famous elm tree that stood in Boston before American Revolution.

The 'Tree of Liberty' at Srirangapatnam was founded in 1794 by French Republican officers with the support of Tipu Sultan.

Water is the important nutrient all organisms need. Humans has almost 60% of their body weight is water. Some organisms have 90% of their body weight is of water.

Van Ki Asha means Hope of forest. Banas river of Rajasthan is known as Van Ki Asha. It passes through Udaipur originating from aravallis. It is the longest river with length 512 kms in Rajasthan having full flow.

Generally, plants absorb dissolved nitrates from soil and convert them into free nitrogen.

• Free nitrogen is simply molecular nitrogen (N2).

• Nitrogen, in its molecular form, consists of two nitrogen atoms bound together with a triple bond.

The first computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous, taking up entire rooms.

National Science Centre is located at New Delhi.