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The given graph shows the changes in level of pollution in an area over a time period.

Which of the following can be inferred from the given graph?

AAt point P a lot of forest land was cleared for human consumption whereas at point Q large scale afforestation was done.
BAt point R a new factory was set up in the area.
CPeople cut down the use of fossil fuels in the interval S - T as compared to its earlier usage.
DIntervals R - S and T - U indicate activities like use of bioinsecticides and biopesticides instead of chemicals in farming, use of public transport instead of private transport, etc.

It is possible to make a meaningful word with the second, the third, the ninth, the tenth, the thirteenth, the fourteenth and the eighteenth letters of the word COUNTERINTELLIGENCE, using each letter only once, except the second letter, which should be used twice, which of the following will be the third letter of that word? If no such word can be formed give 'X' as the answer, and if only two such words can be made give answer 'Y'. And if more than two such words can be formed give answer 'Z'.

A C
B X
C Y
D Z

Humans inherit colour of their eyes from their parents. Brown-eyed couple has three blue-eyed children. Which of the following statements gives correct explanation of this situation?
(i) Each parent has an allele for brown eyes and an allele for blue eyes.
(ii) The allele for blue eyes is recessive.
(iii) The probability that their next child will have blue eyes is 0.75.
(iv) The probability that their next child will have brown eyes is 0.5.

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

A scientist conducted a study on four different species of organisms P, Q, R and S in a terrestrial food chain. He estimated the total number of individuals in the population of each species and the average biomass of each individual.

Which of the following shows the correct relation of these species in a food chain?

AS → R → P → Q
BR → S → Q → P
CQ → P → R → S
DP → Q → R → S

Match column-I with column-II and select the correct option from the given codes.

Shaheen, a class 10 student studied the speed of the given reaction under different conditions.

In experiment I, she added 1 g of MnO₂ (catalyst) to 75 cm³ of 0.4 mol/L H₂O₂ solution at 30°C In experiment II, she added 1 g of MnO₂ to 100 cm³ of 'X' mol/L H₂O₂ solution at 'T' °(C) She recorded her observations and plotted a graph as shown in the given figure.
The values of X and T in experiment II could be respectively


A 0.30 and 35
B 0.40 and 30
C 0.25 and 30
D 0.30 and 30.

Rihan takes an empty half litre plastic bisleri bottle. He opens the lid and fixes his mouth on the opening in such a way that there is no gap between the opening and his mouth. He observes that the bottle crushes inwards when he sucks some air out of the bottle. Which of the following statements is the reason for Rihan’s observation?

AAir pressure inside the bottle increases.
BAir pressure outside the bottle increases.
CAir pressure inside the bottle decreases.
DAir pressure outside the bottle decreases.

Select the best suitable means of communication to get informed or to inform others for the given situations (X, Y and Z).
X : Your sister’s marriage has been fixed and you want all your relatives and friends to be present at the wedding.
Y : Your grandfather, suddenly, suffered from a heart attack and your father is in his office.
Z : Incidence of tsunami had occurred in Japan.

If young crescent Moon is observed on the night of 11th January 20XX, then what is expected to appear on the night of 26th January?

AOld Crescent Moon
BYoung Gibbous
COld Gibbous
DFull Moon