(i) Timber is used to build houses and in making furniture.
(ii) We use wood for these purposes due to their features like durability, stylish finishing and resistance to temperature changes.
(iii) Commercial timber is classified into hardwood and softwood.
(iv) Hardwood is used in construction work and in making furniture.
(v) Softwoods have a wide range of applications such as making plywood and paper making.

(i) Noise pollution affects the environment. Unpleasant or loud sounds distrub us. This is called as noise pollution.
(ii) Loud music the sounds of motor vehicles, fireworks and machines causes noise pollution.
(iii) Continuous noise disturbs our sleep and does not let us to study and also it make stress and health impacts.
(iv) It is also disturb animals, bird and whales in under water.
(v) To reduce noise pollution lower the volume when you watch TV or listen to music.
(vi) Remind drivers not to use the horm too much.
(vii) Avoid fire works and do not speak loudly.

Aim: Soap manufacturing.
Requirements:
i) 35 ml of water.
ii) 10 ml of NaOH.
iii) 60 ml of coconut oil.
Procedure:
i) Cover your work area with old newspaper.
ii) Take 35 ml of water in a jar.
iii) Add 10 gram of concentrated NaOH and allow it to cool.
iv) Then add 60 ml of coconut oil drop by drop and stir it well.
v) On getting dried, soap can be obtained.

(i) Dr. Rajendra Singh is known as "Waterman of India".
(ii) He is a well - known water conservationist and environmentalist.
(iii) His team built rainwater storage tanks, check dams and other timetested as well as path - breaking techniques.
(iv) His team built over 8600 johads to collect rain water for all seasons. It has brought water back to over 1000 villages and revived five rivers in Rajasthan.
Awards:
(i) He won stockholm water prize in 2005, an award known as "The Noble Prize for water".
(ii) Ramon Magsaysay Award in 2001.
(iii) Jamnalal Bajaj Award in 2005.

(i) Potable water is the water which is safe to drink. On an average the human body requires 2-3 liters of water per day for proper functioning.
(ii) It is transparent.
(iii) It is odourless and colourless.
(iv) Cleaned of harmful contaminants.
(v) It is harmless or free from disease causing bacteria.

i) Electromagnets are used in electromagnetic trains.
ii) Electromagnets are magnetised when current flows through them. When the direction of current is changed, poles will be changed.
iii) Magnets are attached at the bottom of the train and rail tracks.
iv) The train is lifted from track upto 10 cm height by the property of some poles that repel each other.
v) By using attraction and repulsion at the same time between the magnets in tracks and bottom of the train it moves forward.
vi) The magnets are controlled by electricity.
vii) There is no friction. So the train can easily attain a speed of 300 km/h.

(a) Bacteria degrade the waste material and convert it into organic minerals.This increases the soil fertility.
(b) While collecting honey from the nectors it leads to pollination which will the first process in reproduction.

When we breathe out, the hot air comes out from our mouth which condenses and gets changed into tiny water droplets and hence the glasses become wet.

If we keep a strong bar magnet above the glass of water, all pins inside the water will come up due to its attraction towards the magnet.

Timbers are used to build houses and make into furnitures.

Aquatic plant ➝ Aquatic insect ➝ Larva ➝ Fish

Ecosystem is a community of living and non-living things that work together.

i) In making black board chalks.
ii) In surgery for setting fractured bones.
iii) For making casts for statues and toys etc.
iv) In construction industry.

people get water from, canals, rivers, wells, ponds, water tanks, hand pipes for various purposes.

Hardware: Hardware is the parts of a computer which we can touch and feel.
Software: Software are programmed and coded applications to process the input information.

Some wastes are degraded by bacteria, fungi and Some insects. It will become as a fertilizer. This type of waste are called as biodegradable waste.
(e.g) Vegetables and fruit wastes, food and garden waste.

(i) Earthworms take organic wastes as food and produce compost castings.
(ii) They improve the soil health and consequently plant health.
(iii) Because of the multitude of services, Earthworms are known as Farmer's friend.

71% of earth's surface is covered with water. The fresh water is only 3%. It remains the same, But the water needed for plants, animals and man is increasing day by day. So we face water scarcity.