Subject :NSO Class : Class 6
Subject :NSO Class : Class 5
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Subject :NSO Class : Class 5
Ans 3:
Class : Class 5
(i) Sedimentation - Sedimentation is a physical water purification process using gravity to remove suspended solid impurities from water. The water is allowed to stand till the suspended solid impurities, which are heavier than water, are pulled down by gravity and settle at the bottom of the container.(ii) Chlorination - Chlorination is the process of adding chlorine, or chlorine compounds such as sodium hypochlorite, to drinking water to disinfect it and kill germs. The addition of chlorine will also oxidize any iron, manganese and/or hydrogen sulphide that are present, so that they too can be removed in the filtration process later on.(iii) Filtration - Filtration is a process of water purification, which is used to separate solid impurities from water by using a filter medium that allows the water to pass through but not the solid impurities. These solid impurities are not heavy, so they do not settle at the bottom, but remain suspended. So, a filter is used to trap them.So, to purify water, it must go through sedimentation (i) first, so that heavier and larger size impurities like sand and dirt, are allowed to settle at the bottom of the container and are removed first. Next, water must go through chlorination (ii), so that bacteria and germs present in water are killed. Any iron, manganese and/or hydrogen sulphide, if present, also get oxidized by chlorine. These can be removed later by the filtration (iii) process, along with other suspended impurities.Hence, the right answer is Option D.
Ans 5:
Class : Class 4
the correct order is 1,3,2 but there is no option like that but if you look at option A you'll find the correct order in a descending order (from back) so if there is no option like 1,3,2 then A should be correct
Ans 8:
Class : Class 5
The correct order is 1-3-2 and there is no option like that .So,I think that it might be a printing error.
Ans 10:
Class : Class 5
The correct option should be - 1-3-2 ( Sedimentation - Filtration - Chlorination )This option is not given. Sedimentation - All the particles settle down as gravity pulls the heavier sediments down.Filtration - It removes the sediments from the water.Chlorination - Process of adding chlorine to water and removing the parasites,bacteria and viruses. Now the water is purified.
Ans 15:
Ans 21:
Class : Class 6
1-3-2 is the correct order as first we should remove all the insoluble impurities and the the soluble impurities.
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Subject :NSO Class : Class 4
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Subject :NSO Class : Class 5
Ans 2:
Class : Class 5
it should be B because bat doesn't have hair or fur. So, it is not common with all animals
Ans 4:
Class : Class 6
Please check the solution, platypus, unlike the other mammals, lays eggs, so option D is correct.
Ans 7:
Class : Class 5
they all are mammals and give birth to young ones whereas dolphin and whales do not have hairs on their body
Ans 10:
Class : Class 6
Why will the answer be D? The animals are dolphin, whale, bat, bear and platypus, and they are all mammals and give birth to young ones. This is a common feature, but the question says to mention the uncommon feature. The answer should be C for sure. The solution given is wrong.
Ans 14:
Class : Class 6
bat has microscopic hair, bear has fur, dolphin has hair when it is a baby, platypus has hair. platypus also lays eggs. so d is the answer
Ans 19:
Class : Class 7
D is correct as only platypus laying egg and not rest. Thus it is not come since 1/4 of them lay eggs.
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Subject :NSO Class : Class 5
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Subject :NSO Class : Class 4
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Subject :NSO Class : Class 8
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Subject :NSO Class : Class 4
Ans 5:
Class : Class 10
please mention the phrase for piercing teeth with the detail solutions not just the answers please make these changes