Questions

Angel, Venezuela

Paramveer Chakra

Second ozone hole was detected over Tibet in the year 2006. 

Ozone is a form of oxygen, acts as a high-altitude atmospheric screen against cancer-causing ultraviolet light.

The main source of these halogens in the stratosphere is photodissociation of man made halocarbon refrigerants, solvents, propellants and CFC's.

Burkina Faso proposed the observance of World Pulses Day on 10th February.

Both the floor and the carpet have the same temperature as both are exposed to the same atmosphere. But the former conducts away the heat from the feet better than the carpet as the latter is a non-conductor. So the feet losing more heat, the floor appears cooler to the feet.

Nitrogenous base: A molecule that contains nitrogen and has the chemical properties of a base.

DNA and RNA ::

The nitrogenous bases in DNA are

Adenine (A),

Guanine (G),

Thymine (T), and

Cytosine (C).

Whereas the nitrogenous bases in RNA are the same, with one exception:

Adenine (A),

Guanine (G),

Uracil (U), and

Cytosine (C).

Let that something be 'x'

From the given data,

x + x/5 = 21

5x + x/5 = 21

6x = 21 x 5

=> x = 17.5

Hence, that something is x = 17.5.