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Pragun goel from Venkateshwar International School, Delhi
Subject :NSO    Class : Class 5

Ans 1:

Rayna Rastogi from The Shri Ram School Aravali , Haryana 122003
Class : Class 5
EXACTLY!

Ans 2:

Agastya Tripathi from dps gurgaon, Gurgaon
Class : Class 4

Ans 3:

Mithul Pranav KB from Narayana Olympiad School Madipakkam, Chennai
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 4:

Mithul Pranav KB from Narayana Olympiad School Madipakkam, Chennai
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:

PRANAV VELDURTI from meridian school madhapur, hyderabad
Class : Class 9

Ans 6:

Navya GUPTA from dps noida, Noida
Class : Class 3

Ans 7:

Srija Das from Sent Joseph Convent Chandannagar, Serampore
Class : Class 10

Ans 8:

Katelyn Asir from Kendriya Vidyalaya, Chennai
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 9:

Rayna Rastogi from The Shri Ram School Aravali , Haryana 122003
Class : Class 5

Ans 10:

niuv from meridian, Hyderabad
Class : Class 6

Ans 11:

Debashree Samanta from DPS BANGALORE , bangalore
Class : Class 6
the order is not 1-2-3. it is 1-3-2. but there is no option

Ans 12:

Suresh Gyanchandani from St. Anselms Pink City Senior Secondary School, Jaipur
Class : Class 5
Correct option should be 1, 3, 2.

Ans 13:

Rayna Rastogi from The Shri Ram School Aravali , Haryana 122003
Class : Class 5

Ans 14:

Swastik Srivastava from Baldwin Boys High School, Bangalore
Class : Class 5
correct order is 1-3-2 but there is no option

Ans 15:

samanvay sinha from School of India, Bangalore, bengaluru
Class : Class 5
please no printing errors

Ans 16:

Navya GUPTA from dps noida, Noida
Class : Class 3

Ans 17:

Rayna Rastogi from The Shri Ram School Aravali , Haryana 122003
Class : Class 5
OMG the correct order isn't even mentioned here!

Ans 18:

Anshu Manglik from Delhi Public School, Gurgaon
Class : Class 7

Ans 19:

VAIBHAV RAI from Cambridge Court High School, JAIPUR
Class : Class 8
The correct order is 1-3-2 but there's no option having it

Ans 20:

Devina kashyap from TPS, Mumbai
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 21:

Hari Govind from Delhi Public School Chandigarh , Chandigarh
Class : Class 6
1-3-2 is the correct order as first we should remove all the insoluble impurities and the the soluble impurities.

Ans 22:

Bhavya from ABC, Delhi
Class : Class 7
the order should be 1-3-2 . there is no option like that. what are these SOF people

Ans 23:

Rayna Rastogi from The Shri Ram School Aravali , Haryana 122003
Class : Class 5

Ans 24:

Devaansh Peddu from LHGS, RAJAHMUNDRY
Class : Class 5
The answer is 1-3-2

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Priyanshu Ku sahoo from KV no 1 Cuttack, Cuttack
Subject :NSO    Class : Class 4

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Kanishk Mukherjee from BDM International, Kolkata
Subject :NSO    Class : Class 5

Ans 1:

Aria Routray from V S Vidyalaya , Sunabeda
Class : Class 5
All of them don't have hair

Ans 2:

harry potter from Hogwarts school of witchcraft and wizardry , london
Class : Class 5
it should be both B and D

Ans 3:

Saumyajyoti Mukherjee from Delhi Public School Bangalore East, Bangalore
Class : Class 3
d

Ans 4:

anika from St Joseph sen sec school Mahoba, Kulpahar
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 5:

Shaurya Gote from KV BSF Dantiwada, S K Nagar
Class : Class 5
DOLPHINS ARE MAMMALES. THEY HAVE TINY HAIRS

Ans 6:

Vidula Malkar from DPYA High school, Mumbai
Class : Class 7
It is written not common then how will the ans be D

Ans 7:

Ahaan Dodiya from Anand Niketan International Sarkhej , Ahmedabad
Class : Class 5
Dolphins do not have hairs and you don't know how to spell " Mammals "

Ans 8:

Ayushree Barman from Sri Sri Academy, Kolkata
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 9:

Ginny Weasley from Hogwarts, London
Class : Class 6

Ans 10:

Hari Govind from Delhi Public School Chandigarh , Chandigarh
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 11:

Aayush from Amrita vidyalayam, Delhi
Class : Class 4
it is written not common and then also it's saying D

Ans 12:

Diya Anilkumar from DPS Bangalore North, Bangalore
Class : Class 5
It’s both b and d

Ans 13:

Samith Ramesh from National public school East, Bangalore , Bangalore
Class : Class 6
Please check the solution, platypus, unlike the other mammals, lays eggs, so option D is correct.

Ans 14:

Saanvi Sa Panda from Rainbow International School, Thane
Class : Class 5
The answer should be B and D.

Ans 15:

Ehan Gowrav from NPS BSK, Bangalore
Class : Class 5
it should be B because bat doesn't have hair or fur. So, it is not common with all animals

Ans 16:

Mukta Pundir from ,
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.

Ans 17:

Dheeraj Thriyambak M from Sri Sankara Senior Secondary School Adyar, Chennai
Class : Class 6
platypus lays eggs! Go search it on google

Ans 18:

ADRIJA SAHA from DPS RANIPUR, Haridwar
Class : Class 6
In platypus they lay eggs

Ans 19:

D M Sarvesh from Narayana Group of Schools, Mogappair
Class : Class 4
Both B and D are correct

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Anupama from Gurukula international school , Javagal
Subject :NSO    Class : Class 3

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Kanishk Mukherjee from BDM International, Kolkata
Subject :NSO    Class : Class 5

Ans 1:

Riddhiman Bose from Don Bosco School, Kolkata
Class : Class 5

Ans 2:

Devdarsh hero from HOLY GRACE, Mala
Class : Class 6
a duck cannot fly !

Ans 3:

aarav agarwal from Bal Bharati Public School Manesar, Manesar
Class : Class 5
b is the correct answer

Ans 4:

Sarthak Singh from Podar International School, Chinchwad, Pune
Class : Class 5
Duck can't fly

Ans 5:

Jesslin Hephzibah from Bishop cotton girls school, bangalore
Class : Class 5
Which is the correct answer for this question/

Ans 6:

SOUVAGYA SAHA from De Nobili School, DHANBAD
Class : Class 10

Ans 7:

Smita De from Bishop Cotton Girls School, BANGALORE
Class : Class 5
DUCKS CAN NOT FLY !!!

Ans 8:

Vedant Pandey from Manav Rachna International School, Gurgaon
Class : Class 5
A duck cant fly

Ans 9:

Reyan from , Chandigarh
Class : Class 2
ducks can fly but goose can fly more further

Ans 10:

Mukta Pundir from ,
Class : Class 7
Most ducks can actually fly except a few of them.

Ans 11:

Shreejith from EuroSchool , Bangalore
Class : Class 7
Only few ducks fly. Maybe this is why it is B

Ans 12:

Swastik Srivastava from Baldwin Boys High School, Bangalore
Class : Class 5
duck can not fly

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adhiraj chaudhary from apeejay school noida, noida
Subject :NSO    Class : Class 4

Ans 1:

Bidyashree Panda from Royal Concord International School Begur, Bangalore
Class : Class 4
d is the correct ans.These all places are a great tourist attraction.

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soham mehta from St Andrews school Bowenpally, Secunderabad
Subject :NSO    Class : Class 8

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Mishika Singh from EISB, Bangalore
Subject :NSO    Class : Class 4

Ans 1:

Advay Dhua from Delhi Public School NOIDA, Noida
Class : Class 5

Ans 2:

Bidyashree Panda from Royal Concord International School Begur, Bangalore
Class : Class 4
is piercing teeth a canine?

Ans 3:

Shriyansh Kore from Innovative Public school Borawade, Kolhapur
Class : Class 4
what are piercing teeth?

Ans 4:

Mishika Singh from EISB, Bangalore
Class : Class 6

Ans 5:

Bismeet Chetia from NPSI Singapore, Singapore
Class : Class 4
Piercing teeth is same as tearing teeth

Ans 6:

Gunnika from MVN, Faridabad
Class : Class 3
piercing teeth and canines are the same thing in humans

Ans 7:

Shaurya Shinde from Goldcrest High Vashi, Navi Mumbai
Class : Class 8
what are piercing teeth

Ans 8:

Mishika Singh from EISB, Bangalore
Class : Class 6
What are piercing teeth?

Ans 9:

Aadya from Vidyashilp , Bangalore
Class : Class 10
please mention the phrase for piercing teeth with the detail solutions not just the answers please make these changes

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Mishika Singh from EISB, Bangalore
Subject :NSO    Class : Class 4

Ans 1:

Deveshi Sachdev from venkateshwar international school, New Delhi
Class : Class 6

Ans 2:

Ramvaros Kumar from Dps ranipur, haridwar
Class : Class 5

Ans 3:

Gunnika from MVN, Faridabad
Class : Class 3
ANSWER is D !!

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Mishika Singh from EISB, Bangalore
Subject :NSO    Class : Class 4

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