Rayon is made from cellulose obtained from wood pulp. Nylon, polyester and acrylic are made entirely of chemicals. Nylon, polyester are made up of repeating units of amides and esters respectively

Plastic is non-biodegradable, it takes several years to decompose. Thus cause environmental pollution. So, we should avoid use of plastics

(a) Synthetic fibres melt on heating. If the clothes catch fire, it can be disastrous. The fabric melts and sticks to the body of the person wearing it. So, she advised her not to wear synthetic clothes while working in kitchen.
(b) Sunita loves to wear clothes which are made up of synthetic fibres because these clothes dry up quickly, durable, less expensive, readily available and easy to maintain.
(c) Sunita is obedient, smart, scientific and having learning attitude. Her mother is scientific and caring.

Manufacturing synthetic fibres is actually helping conservation of forests because the natural fibres require raw materials from plants and animals. So, they lead to cutting of trees and killing of animals. On the other hand, synthetic fibres are made of chemicals obtained from coal and petroleum products. Thus, manufacturing of synthetic fibres is actually helping conservation of forests.

Advantages of storing foods in plastic containers are as follows:
(i) Plastics do not react with food items.
(ii) Plastics are strong, light and durable.
(iii) Plastic containers are airtight.
(iv) They are easy to handle.

The fibres obtained from natural sources, i.e. plants and animals are called natural fibres. So, cotton, wool and silk are natural fibres.

Polyester absorbs very little water hence, it does not absorb sweat, so it becomes unsuited for summer.

(i) Thermoplastics
(ii) Thermosetting plastics

4Rs stand for Reduce, Reuse, Recycle and Recover.

Since, wool is made from hair of sheep, it gives smell of burning hair.

(a) Nikita was aware that plastic is a non-biodegradable material. Disposal of plastic is a major problem. It is not easily decomposed by natural process. So, to avoid the use of plastic she prefer to take steel lunch box.
(b) No, plastic materials are not environment friendly since, it takes several years to decompose and causes environmental pollution. Besides, in the burning process it releases lots of poisonous fumes (gases) into the atmosphere causing air pollution.
(c) Nikita is very aware, sensible and intelligent girl.

The importance of synthetic polymers in our life are as follows:
(i) Nylon It is used for making ropes for rock climbing, fishing nets, raincoats, parachutes and tyre cords, etc.
(ii) Acrylic It is used for sweaters, track suits, linings for boots and gloves and in furnishing fabrics and carpets.
(iii) Terylene It is used in textile industry to make clothes like sarees, tapestry and dress material. It is also mixed with natural fibre like cotton and wool to make more variety of clothes.
(iv) Plastics It is used to store food item, water, milk, pickles, dry food, etc. This is because of light weight, low price, good strength and easy handling as compared to metals. Plastics are used in cars, aircrafts and spacecrafts.