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Subject :NSO    Class : Class 3

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Subject :NSO    Class : Class 8

A few healthy gram seeds are placed in each of the three pots X, Y and Z containing same type of soil. The soil in pot X is mixed with some green leaves. The soil in pot Y is mixed with old cow dung while soil of pot Z is mixed with urea. Pots are watered regularly and given proper environment for plant-growth. Which of the following will be observed after 10 days?

A Lot of growth in Z with replenishment of all the nutrients.
B Lot of growth in X without replenishment of any nutrient.
C Lot of growth in Y with replenishment of the nutrients.
D Both (A) and (C)


Ans 1:

Class : Class 8

Ans 2:

Class : Class 9
As per the activity mentioned in NCERT and my own research, the most appropriate answer should be A, because fertilizers boost plant growth and are nutrient specific, meaning they replenish the nutrients.

Ans 3:

Class : Class 8
It should be D as both manure and fertiliser have nutrients

Ans 4:

Class : Class 8

Ans 5:

Class : Class 9
Fertilizer can be both acidic or basic. Some fertilizers have Urea, Ammonium Nitrate as constituents due to which they are acidic. However salts of Potassium such as Potassium Nitrate and Phosphate are also used that are strong bases.

Ans 6:

Class : Class 9
The answer should be (A) because Urea is an acid and contains high amounts of Hydrogen and Nitrogen. It is also considered as a fertilizer because fertilizer is an acid just like urea and also fertilizer contains high amounts of hydrogen and nitrogen. Fertilizer also allows the maximum plant-growth. So, it should be (A).

Ans 7:

Class : Class 8
should be option d

Ans 8:

Class : Class 8
a

Ans 9:

Class : Class 9

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Subject :NSO    Class : Class 2

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Subject :NSO    Class : Class 6

Ans 1:

Class : Class 6

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 5

Ans 2:

Class : Class 5
13

Ans 3:

Class : Class 5
13

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Subject :NSO    Class : Class 8

Ans 1:

Class : Class 8

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Subject :NSO    Class : Class 3

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Subject :NSO    Class : Class 2

Ans 1:

Class : Class 2
aya

Ans 2:

Class : Class 2

Ans 3:

Class : Class 2

Ans 4:

Class : Class 2
Ans= Pond

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Subject :NSO    Class : Class 3

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Subject :NSO    Class : Class 8

Ans 1:

Class : Class 8
In my opinion, the answer to this question should be option (X) - Can’t be determined. This is because there are two orders of executives (on the basis of reaching the office first). Firstly, consider the order: S, Q, U, P, T, W, R. This order fulfills all the criteria: firstly, R is the last person to reach the office; secondly, U reaches immediately before P; thirdly, P is consecutively followed by T, and then T is followed by W; finally, S is not immediately followed by U, and not at the second last position. According to this order, the person who reaches office fourth is P. However, considering the order: U, P, T, W, S, Q, R, the fourth person is W. This order also fulfills all criteria, and thus is a suitable order. Thus, there are two answers to this question: P, and W. Therefore, the answer should be option (X) - can’t be determined. Option (D), as given in the solution, is an incorrect option, due to phrasing. "None of these" suggests that there is one other 'definite' answer, while "Can't be determined" suggests that there is 'more than one answer', or 'an unknown answer'. The confusion in this question might arise from the fact that the question's phrase "U reaches...but does not immediately follow S.". This phrase seems to imply that U follows S, just not immediately. However, this implication is an inference we derive from common sense and pragmatic thinking, not of rational and logical decision making. Just because U does not immediately follow S, it does not mean U follows S, it could also mean S follows U, because this does not contradict the phrase 'U reaches....but does not immediately follow S'. That is probably why, in the solution, the order S, Q, U, P, T, W, R is given, but the order U, P, T, W, S, Q, R isn't.

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