A democratic country needs a Constitution because:

• It lays out the important guidelines that govern decision making within the various societies of the country.
• It lays down the ideals that form the basis of the kind of country that its citizens aspire to live in.
• It serves as an asset of rules and principles as the basis by which the country has to be governed.
• It provides rules to safeguard the interests of minorities and prevent any kind of domination by the majority on minorities.
• It lays down rules that guard against the misuse of power by any politician leader.
• It also provides rights to its citizens and protects their freedom.

The preface or introduction to our Constitution is known as the Preamble. The Preamble indicates the source, the objectives and the underlying spirit of our Constitution.

Erythrocytes or red blood cells have a red coloured, iron-containing complex protein, called as hemoglobin, hence the colour and name of these cells. A healthy individual has 12 - 16 gm of hemoglobin in every 100 ml of blood. These molecules play a significant role in the transport of respiratory gases.

Hoe is a tool used for loosening soil. It is made of wood or iron. A strong iron plate attached to the long rod acts like a blade and helps to loosen the soil. It is also pulled by animals.

The definition of fusion is the act of melting or blending two or more separate things into one. An example of fusion is creating a dinner that combines Indian and Japanese elements.For example, uranium can fission to yield strontium and krypton. Fusion joins atomic nuclei together. The element formed has more neutrons or more protons than that of the starting material. For example, hydrogen and hydrogen can fuse to form helium.

Microorganisms- A living organism that is very minute to be seen by the naked eye, especially a single celled organism, such as a bacterium is called microorganism. Microorganisms are classified into four major groups mainly bacteria, fungi, protozoa and some algae.

Leveling is a process  to make (a surface) level, even, or flat: to level ground before building. to raise or lower to a particular level or position; to make horizontal.

Modern methods of irrigation

Modern methods of irrigation being able to overcome the limitations of traditional methods are encouraged these days. Some of the modern methods of irrigation are:

Sprinkler system

In this system, there are perpendicular pipes with rotating nozzles on top. These pipes are joined to the main pipeline. Water flows through main pipeline under pressure by a pump. Water escapes from the nozzles & reaches the field.

Drip system

In this system, water falls drop wise near roots. Therefore, there is no wastage of water. This method is very good for areas with less water.

Traditional methods of Irrigation

Different types of irrigation methods are used depending on the different water resources like wells, canals, river lift systems and tanks.

Many of these traditional methods of irrigation like wells involve groundwater extraction. Tanks act as artificial reservoirs of water to be used for irrigation.

There are certain disadvantages associated with traditional methods of irrigation like:

• Too much human labor involved
• Less efficient due to uneven distribution of water
• Wastage of water

Let the first number be x
second number be (x+15) // one exceed other by 15 //
sum of the number is  given by x+(x+15) = 95
x+x+15=95
2x+15 = 95
2x =95-15
2x = 80
x=80/2
x =40
first number x=40, second number x+15 = 40+15= 55
The numbers are 40 and 55.

Rabi crops are the crops which are sown in winter season (Oct - Feb) and harvested in spring season (Mar - Apr) in South Asia, including India. These are mostly agricultural crops. Examples are maize, barley, wheat, etc.

When an alkali is dissolved in water, the solution formed is known as alkaline solution. They can be formed in the laboratory or via natural processes also like erosion. Alkaline solution is basic in nature so used in the laboratory, industry etc. to make chemical reactions basic or neutral.

Anaerobic respiration is a type of cellular respiration where respiration takes place in the absence of oxygen. The process is also called fermentation. They will not enter into TCA cycle or ETS. Here partial glycolysis results in pyruvic acid. Pyruvic acid undergoes further reduction and gives carbon dioxide and ethanol along with ATP. This is known as alcoholic fermentation.
During anaerobic conditions, inside animal muscle cells, fermentation takes place and produces lactic acid and ATP. This is lactic acid fermentation. The total sum of ATP molecules produced during fermentation is very less as compared to aerobic respiration.

Actual resource - They are resources which have been put to good use and their total quantity is known

Example: Water, oil, trees, fish, minerals