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ABHAY AGARWAL from ,
Subject :NSO    Class : Class 4

Rohit performed an experiment wherein he set up three test tubes as shown in the figure. Select the INCORRECT statement regarding this.


ATest tube P will have most carbon dioxide after three hours.
BTest tube Q will have least oxygen after three hours.
COrganisms in test tube R will survive for a longer time as compared to organisms in test tubes P and Q.
DNo oxygen will remain in test tube P after some time.


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Ans 1:

Ainesh das from Chrysalis, Bangalore
Class : Class 4

Ans 2:

Bushra aslam from uttam, Ghaziabad
Class : Class 4

Ans 3:

avighna wuthoo from The bishop school , PUNE
Class : Class 5

Ans 4:

PARTH MEHTA from Nov rachna school, Vadodara
Class : Class 3

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ABHAY AGARWAL from ,
Subject :NSO    Class : Class 4

Ans 1:

adhiraj chaudhary from apeejay school noida, noida
Class : Class 3

Ans 2: (Master Answer)

Admin from revisewise, Noida
Class : Class 1
The correct answer is D.

Ans 3:

adhiraj chaudhary from apeejay school noida, noida
Class : Class 3
the correct answer is d

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Pradanya from KV IIT, Chennai
Subject :NSO    Class : Class 6

Ans 1:

Rahil from Delhi Public School Faridabad, Faridabad
Class : Class 7

Ans 2:

Agustya vaid from Somerville school vasundhara enclave, Delhi
Class : Class 7
the answer is d because the field lines of a magnet always travle from north to south

Ans 3:

Ishaan Das Roy from Sri Chaitanya Techno School, Bengaluru
Class : Class 8

Ans 4:

kpks14 from RIMT World School, Chandigarh
Class : Class 7

Ans 5:

Agustya vaid from Somerville school vasundhara enclave, Delhi
Class : Class 7
understood?

Ans 6:

Veda Dua from DPS R K PURAM, New Delhi
Class : Class 6

Ans 7:

Raghav Aggarwal from CAMBRIDGE SCHOOL INDIRAPURAM, INDIRAPURAM
Class : Class 7

Ans 8:

Winka Jayaprakash from Sri Vijay Vidyasharam , Hosur
Class : Class 9
the field line travels from north to south

Ans 9:

Agustya vaid from Somerville school vasundhara enclave, Delhi
Class : Class 7

Ans 10:

Ishaan Das Roy from Sri Chaitanya Techno School, Bengaluru
Class : Class 8

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Akshay Kumar from BVM, Chennai
Subject :NSO    Class : Class 7

Ans 1:

Arnav from Gyan Bharati School, New Delhi
Class : Class 8

Ans 2:

Amol Athawale from WoodRidge High, Mumbai
Class : Class 8

Ans 3:

N Sankar Narahari from Madhavakripa English Nursery and Higher Primary School, Manipal
Class : Class 7
here option c holds true because in option a and b we can make an exception with pulmonary artery and vein.

Ans 4:

Amol Athawale from WoodRidge High, Mumbai
Class : Class 8

Ans 5:

Arnav from Gyan Bharati School, New Delhi
Class : Class 8
Yes, the answer is option "C". It is not true that arteries will always carry oxygenated blood and the veins will always carry deoxygenated blood (pulmonary vein and artery).

Ans 6:

Aditya Sai Vemparala from Amanora school, Pune
Class : Class 8
C

Ans 7:

Mayank Gupta from Kulachi Hansraj Model School, New Delhi
Class : Class 8

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chandra Deb from ,
Subject :NSO    Class : Class 5

Ans 1:

Bhavya Agrawal from Cambridge Court High School , JAIPUR
Class : Class 5
you are correct Pragun goel . my answer is also a.

Ans 2:

Shriya Sreekrishna from BLUEBELLS SCHOOL INTERNATIONAL, New Delhi
Class : Class 7

Ans 3:

Pragun goel from Venkateshwar International School, Delhi
Class : Class 6
sea snakes also breathe through skin so option 1 should also be correct.

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Shuvangi Das from Vivekananda mission school, haldia
Subject :NSO    Class : Class 3

Ans 1: (Master Answer)

Admin from revisewise, Noida
Class : Class 1
The correct answer is C.

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Rio Choudhury from South Point High School, Kolkata
Subject :NSO    Class : Class 7

Ans 1: (Master Answer)

Admin from revisewise, Noida
Class : Class 1
Molars and Premolars are mainly used to chew the food.

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vaibhav from , Faridabad
Subject :NSO    Class : Class 7

Ans 1:

Sporangia from SBOA Global, Chennai
Class : Class 7
The solution: Enzyme X works best and increases the rate of reaction at an acidic pH (less than 7) of about two2️⃣ ! Enzyme Y is very very very very very very very very very very very very very very very very very efficient @ slightly acidic pH i.e., slightly less than seven!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Enzyme Z is most efficient at an alkaline pH (more than 7!!!). And alkali means a base which is soluble in water. In humans, gastric juice of stomach (a J-shaped bag with thick inner walls. Meh.) has pH in the range of 1.5-2.5, where enzymes such as pepsin, rennin etc. carry out the digestion of food. Thus, enzyme X can be found in stomach. Similarly, the saliva in the mouth of humans has sliiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiightly acidic pH of 6.8, where salivary amylase enzyme is moooooooooooooooooooooooooooooooooooooooost effective! Thus, enzyme Y can be found in the buccal cavity. Small intestine has slightly alkaline pH of 7.8, where enzymes such as trypsin help in digestion of food. So, enzyme Z can be found in duodenum. Morus Alba is the scientific name of mulberry.

Ans 2:

aryan vir from lotusvalley international school gurugram, Gurgaon
Class : Class 7

Ans 3:

Sporangia from SBOA Global, Chennai
Class : Class 7
Is D. ✔

Ans 4:

aryan vir from lotusvalley international school gurugram, Gurgaon
Class : Class 7

Ans 5:

Tanushree from Asian International School, Colombo
Class : Class 7
Can someone pls send the explanation of why it's D🙏

Ans 6:

Arush from Anandi Public School, Udgir
Class : Class 3
such questions r always confusing.................

Ans 7:

aryan vir from lotusvalley international school gurugram, Gurgaon
Class : Class 7

Ans 8:

Arush from Anandi Public School, Udgir
Class : Class 3

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ABHAY AGARWAL from ,
Subject :NSO    Class : Class 4

Refer to the given paragraph and table and answer the following questions.
Neha took 100 gm each of three types of soil, X, Y and Z, in three separate pots with hole at the bottom. The amount of water that was poured in the soil pot, just before it started dripping from the bottom hole, is tabulated here.

The soil that is mixture of clay, sand, humus and is usually very good for growth of most plants is __________.

A X
B Y
C Z
D Cannot be determined


Ans shd be D (Cannot be determined)

Ans 1:

ABHAY AGARWAL from ,
Class : Class 3

Ans 2:

ANURADHA NAIR from SANDEEPANI VIDYA NIKETHAN SCHOOL, Thrissur
Class : Class 5
B IS THE ANSWER ANURADHA NAIR 4C

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ABHAY AGARWAL from ,
Subject :NSO    Class : Class 4

Ans 1:

Anika from Alphabets, Chennai
Class : Class 4
Chloro-fluro-carbon

Ans 2:

BV Karthikeya from Sentia, Hyderabad
Class : Class 5
I GOT IT CORRECT

Ans 3:

Deepika from Vibgyor high, Mumbai
Class : Class 1
It should be CFCS

Ans 4:

BV Karthikeya from Sentia, Hyderabad
Class : Class 5

Ans 5:

Abhinav Kulkarni from National Centre For Excellence, Bengaluru
Class : Class 4
the ans should be CFC

Ans 6:

Nishchita Singh from Gems Modern Acadmey , Dubai
Class : Class 4
The answer is B as when we use electricity fuel gets burnt and so it produces carbon dioxide.

Ans 7:

ABHAY AGARWAL from ,
Class : Class 3

Ans 8:

Adit Aggarwal from Vibgyor High, Bengaluru
Class : Class 5
The answer was supposed to be CFC .

Ans 9:

SRISANTH from Edify, Tirupathi
Class : Class 5
Actually it is b ,as a is CNG(compressed natural gas which is a energy source that is not a greenhouse gas

Ans 10:

Tanirika Bansal from DPS Faridabad, Faridabad
Class : Class 4
CFCS should be correct answer but I got it right

Ans 11:

SAURISH from Podar, Mumbai
Class : Class 4
THE OPTION SHOULD HAVE BEEN CFC OR WE CAN TAKE THE OPTION D [NITROGEN] BUT IT IS SHOWING WRONG

Ans 12:

Visakha Dhar from GD Goenka, jhajjar
Class : Class 3
the correct answer is CFCs .but is not mention in the option.

Ans 13:

Rehaan Sejwal from Gyan Bharati school, Delhi
Class : Class 5

Ans 14:

Shaurya Veer from DPS, Palampur
Class : Class 5
The correct answer should be CFC

Ans 15:

Mohammad Shahid from Dayawati Modi International Maple Bear, Modipuram, Meerut 250110, Meerut
Class : Class 4
how the released gas from refrigerator is CO2

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