1)Synthetic fibres are very strong
2)Synthetic fibres are more durable:They have high resistance to wear and tear.Due to this,clothes made of synthetic fibres are very durable.
3)Synthetic fibres   absorb very little water:Clothes made of Synthetic fibres dry very quickly. Clothes made from natural fibres do not dry quickly.
4)Synthetic fibres are wrinkle resistant:The clothes made of Synthetic fibres do not get crumpled easily during washing or wear.
5)Synthetic fibres are light weight
6)Synthetic fibres are extremely fine:The fabric made from from synthetic fibres have a very smooth texture whereas natural fibres are not so fine.

Crop rotation is considered good agricultural practice for the following reasons :
1.it maintains fertility of the soil. for example a legume rotation is very useful because leguminous plants give nitrogen to the soil, so farmer gets higher yields.
2. Weeds are also destroyed as continuous weeding is done .
3. It also helps in control of insects and diseases in plants.

The living organisms that you fail to see with your eyes and which can be seen only with the microscope are called as micro-organisms. These microorganisms are very small and widely found.
The study of microorganisms is known as microbiology

Its mainly done to prevent seed-borne diseases.However,seeds may germinate,even if not treared with fungicides solution.
Fungicide seed treatment protects seeedlings from both seed-borne pathogen as well as soil-borne pathogens.

Drip irrigation, also known as trickle irrigation or micro irrigation or localized irrigation, is an irrigation method that saves water and fertilizer by allowing water to drip slowly to the roots of plants, either onto the soil surface or directly onto the root zone, through a network of valves, pipes, tubing, and emitters. It is done through narrow tubes that deliver water directly to the base of the plant.

All fabrics are obtained from fibres and fibres are obtained from artificial or man-made sources.  It consists of small unit or a polymer which is made from many repeating units known as monomers. Example: rayon, nylon, polyester, etc.

The ploughed soil is levelled by pressing it with a wooden leveller so that the top soil is not blown away by wind or drained off by water. The levelling of ploughed fields prevents the top fertile soil from being carried away by strong winds or washed away by rain water.

The modern method compensates disadvantages of traditional methods and thus helps in the proper way of water usage. The modern method involves two systems: Sprinkler system and Drip system. A sprinkler system as its name suggests sprinkles water over the crop and helps in an even distribution of water. This method is much advisable in areas facing water scarcity. Here a pump is connected to pipes which generate a pressure and water is sprinkled through nozzles of pipes. In Drip system, water supply is done drop by drop exactly at roots using a hose or pipe. This method can also be used in regions where water availability is less.

Crop rotation  is the practice of growing two or more varieties of crops in the same region in sequential seasons. A common example of crop rotation is to cultivate maize followed by soyabean. The crops selected, vary in nutrient requirements. This ensures complete and uniform utilization of nutrients thereby preventing crops from pests and diseases, without causing loss to soil fertility.

The various tasks performed by a farmer to produce a good crop are called agricultural practices. The various agricultural practices which are carried out at various stages of crop production are:

1. Preparation of soil
2. Sowing
3. Adding manure and fertilisers
4. Irrigation
5. Removal of weeds
6. Harvesting
7. Storage of food grains.

Agricultural Implements:

Before sowing the seeds, it is necessary to loosen and turn the soil in the fields as to break it to the size of the grains which is done with the help of three main implements or tools – plough, hoe and cultivator.

Plough: Plough is a large agricultural implement which is used for ploughing or tilling in the fields.

Hoe: It is an agricultural implement used for removing weeds, and loosening and turning the soil.

Cultivator: The cultivator is a tractor driven agricultural implement which is used for loosening and turning the soil in the fields quickly.

Thermoplastics Thermosetting plastics
1.These are the plastics which get deformed easily
on heating and can be bent easily.
1.These are the plastics which once module cannot
be softened by heating.
2. These are used for manufacturing toys, combs
car grills and various types of containers.
2. Bakelite are used for making electrical switches, handles of various utensils etc. Melamine are used for making floor tiles, kitchen wares and fabrics which resist fire.
3 Example: Polythene, and PVC(Poly vinyl chloride)

3. Example: Bakelite and melamine

Soil is composed of distinct layers. The rotting matter in the soil is called humus. A vertical section through the soil showing the different layers of soil is called soil profile. Soil profile consists of three different layers of soil.

Static friction is a force that keeps an object at rest. It must be overcome to start moving the object. Once an object is in motion, it experiences kinetic friction. ... The maximum force of static friction is μs times the normal force on an object. The frictional force opposing the motion of the crate is equal to the applied force but acting in the opposite direction. This frictional force is called static friction. ... When the applied force is larger than the maximum force of static friction the object will move.