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Subject :NSO    Class : Class 9

Ans 1: (Master Answer)

Class : Class 1
The correct answer is D.

Ans 2:

Class : Class 9

Ans 3:

Class : Class 9
i have got C

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Subject :NSO    Class : Class 4

Ans 1:

Class : Class 7
B) West

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 7

Ans 2:

Class : Class 6
this question is so hard

Ans 3:

Class : Class 5
C is correct

Ans 4:

Class : Class 6
Observe the given diagram carefully which shows a reflex arc. The diagram is show a finger touching the flame of the burning candle. The Sensory Neuron P takes the message of the burning finger to the Relay Neuron R in spinal cord. The Motor Neuron Q takes the message from the Relay Neuron R to the related muscle to act accordingly and pull the finger away. Now, if the orientation of Motor Neuron Q is changed (red arrow) and made as that of Sensory Neuron P, that means message from Motor Neuron Q will go from Muscle to the Relay Neuron R. Now, let’s check the following options to see what will happen: A.All voluntary movements of body including reaction to heat will stop. ----- Incorrect. Reaction to heat is an involuntary reflex response. It will stop if the orientation of Motor Neuron Q is changed. But voluntary movements of the body, which are in control of our brain, will go on. B.The sensory receptor will not get stimulus from the candle. ----- Incorrect. The orientation of Sensory Neuron P is still the same, so sensory receptors in spinal cord will continue to get the stimulus of heat from the candle. C.The motor organ will not be able to get instructions from the spinal cord. ----- Correct. The orientation of Motor Neuron Q has been changed, so instruction from spinal cord will not reach the motor organ (muscle). It will go from muscle to the spinal cord instead. D.None of these ----- Incorrect. Hence, the right answer is Option C.

Ans 5:

Class : Class 7

Ans 6:

Class : Class 5

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 5
C

Ans 2:

Class : Class 5
ccccccccccccc

Ans 3:

Class : Class 5
The answer is C Because Tadpoles breath through gills but gills are not given in the grid

Ans 4:

Class : Class 5
Ans- C

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 6
The explaination of this question is not complete.SOF please edit it.

Ans 2:

Class : Class 6
B

Ans 3:

Class : Class 6
b

Ans 4:

Class : Class 6

Ans 5:

Class : Class 5
b

Ans 6:

Class : Class 5
b

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Subject :NSO    Class : Class 6

The different steps of vermicomposting are given below randomly.
(i) Spread sand on the floor of the pit
(ii) Place red worms in the pit
(iii) Cover with a grass
(iv) Sprinkle water to keep it moist
(v) Dig a pit in a suitable place
(vi) Add vegetable peels and fruit waste in the pit
Which of the following represents the correct sequence of steps?

A (v) → (vi) → (i) → (iii) → (ii) → (iv)
B (v) → (i) → (vi) → (iii) → (iv) → (ii)
C (v) → (i) → (iii) → (vi) → (ii) → (iv)
D (v) → (ii) → (iii) → (iv) → (i) → (vi)


Ans 1:

Class : Class 8
in a much better way First we have to dig the ground. (v)| Then we spread sand on the floor of the pit so that the pit remains open for a longer time. (i)| Then we can add the waste we planed to throw in the pit. (vi) | We have to then cover with grass so that the pit remains closed. (iii) | Moisture is required for wastes to decompose. (iv) | We can later place red worms, as they are very good decomposers_ to speedthe decomposing proccess. (ii)|

Ans 2:

Class : Class 6
option B

Ans 3:

Class : Class 8
First we have to dig the ground. (v) Then we spread sand on the floor of the pit so that the pit remains open for a longer time. (i) Then we can add the waste we planed to throw in the pit. (vi) We have to then cover with grass so that the pit remains closed. (iii) Moisture is required for wastes to decompose. (iv) We can later place red worms, as they are very good decomposers_ to speedthe decomposing proccess

Ans 4:

Class : Class 8
in a much better way First we have to dig the ground. (v) Then we spread sand on the floor of the pit so that the pit remains open for a longer time. (i) Then we can add the waste we planed to throw in the pit. (vi) We have to then cover with grass so that the pit remains closed. (iii) Moisture is required for wastes to decompose. (iv) We can later place red worms, as they are very good decomposers_ to speedthe decomposing proccess. (ii)

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Subject :NSO    Class : Class 4

Ravi set up an experiment as shown in the given figure.The figure shows five identical balls being suspended on a rod by strings of different lengths. Ravi then cut all five strings at the same time and the balls were allowed to fall freely to the ground.

Which of these statements holds true for this experiment?

ABall ‘b’ had the greatest impact on the ground.
BBall ‘a’ had less gravitational potential energy than ball ‘c’ at the start.
CBall ‘d’ had the most gravitational potential energy at the start.
DBalls ‘a’ and ‘e’ had different amounts of gravitational potential energy at the start due to their different positions along the rod.


Ans 1:

Class : Class 7
The answer is [A]

Ans 2:

Class : Class 7
A) Ball ‘b’ had the greatest impact on the ground.

Ans 3:

Class : Class 5
aaa aaa aaa

Ans 4:

Class : Class 4
A

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Subject :NSO    Class : Class 6

Which of the following statements are true about acid rain ?
(i) Acid rain has harmful effects on the living beings.
(ii) Acid rain mainly comprises of H2SO4 and HNO3.
(iii) Greenhouse gases are mainly responsible for causing acid rain.
(iv) Acid rain causes damage to buildings.

A (i) and (ii) only
B (i) and (iii) only
C (i), (iii) and (iv) only
D (i), (ii) and (iv) only


but here option C is also true ,so there have the option as 'all of these'.

Ans 1:

Class : Class 3
D

Ans 2:

Class : Class 6
all are correct

Ans 3:

Class : Class 6
ans is also D

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Subject :NSO    Class : Class 7

Kirti kept a metal spoon in a glass jar filled with pickle for a few days. She observed that there were holes in the spoon. What could be the possible reason for this?

A Oil present in pickle dissolves the metal.
B Oil present in pickle liberates a gas in which metal gets dissolved.
C Metal reacts with acid present in pickle to form salt hence, metal gets dissolved.
D The glass reacts with metal to give acid which dissolves the metal.


i didnt get this . answer says acid reacts with metal to form salt but acid reacts with metal to form hydrogen can you help me ?

Ans 1:

Class : Class 7

Ans 2:

Class : Class 7
C Metal reacts with acids

Ans 3:

Class : Class 7
C Metal reacts with acids

Ans 4:

Class : Class 7
Answer is C as metal react with acid to form salt and hydrogen both

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 3
richa is also wrong as chipko movement started in 1927

Ans 2:

Class : Class 8
It started in '1973', NOT in '1927' you have got your reference wrong. The question says 1974 which is a year wrong so I think they made a mistake while preparing the questions.

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