Argon is most the most abundant Rare Gas in the atmosphere. Its elemental symbol is Ar. 

A small organic molecule (sugars or amino acids), several of which may be bonded together to form a chain called a polymer.

In computing, the expansion card or board or accessory card is a printed circuit board that can be inserted into an electrical connector or expansion slot, on a computer motherboard, to add functionality to a computer system via the expansion bus.

There are 8 different types of Soils present in India. They are primarily differentiated on the basis of composition and structure. They are ::

1.  Alluvial soils, 

2.  Black soils,

3.  Red soils,

4.  Laterite and Lateritic soils,

5.  Forest and Mountain soils,

6.  Arid and Desert soils,

7.  Saline and Alkaline soils and

8.  Peaty and Marshy soils.

Unit digit of this expression is always 1 as the base ends with 1. 

For the tenth place digit we need to multiply the digit in the tenth place of the base and unit digit of the power and take its unit digit.

i.e, tenth place digit in 2151 is 5 and

tenth place digit in power 415 is 1

And the units digit in the product of 5 x 1 = 5

Therefore, last two digits of 2151415 is 51.

• Cactus spines are also known as modified bud scales, which are also called modified leaves.

• Cactus spines occur in clusters in the axil of leaves.

Ethylene is used for Artificial Ripening of Green Fruit.

• Calcium carbide is also used in some countries for artificially ripening fruit. When calcium carbide comes in contact with moisture, it produces acetylene gas, which is quite similar in its effects to the natural ripening agent, ethylene

Orographic precipitation or Rain produced when moist air is lifted as it moves over a mountain range. As the air rises and cools, orographic clouds form and serve as the source of the precipitation, most of which falls upwind of the mountain ridge.

Some also falls a short distance downwind of the ridge and is sometimes called spillover. On the lee side of the mountain range, rainfall is usually low, and the area is said to be in a Rain Shadow.