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The intensity of sound wave gets reduced by 10% on passing through a slab. The total reduction in intensity on passing through three consecutive slabs is

A30%
B70%
C27.1%
D72.9%

World Environment Day is celebrated on _______.

A1st December
B23rd April
C1st July
D5th June

The given figure represents the distance between the three objects. Which of the following will occur if Moon and Sun interchange their position?



AAll the water bodies on the Earth will dry up.
BLife on the Earth will no longer exist.
CDays will be shorter on the Earth.
DBoth A and B

Select the odd one on the basis of habitat.
A
B
C
D

Two persons X and Y are standing at a distance of 100 m from a high wall as shown in the given figure. When X gives a clap, the time interval between the two (direct and reflected) sounds heard by Y is 0.2 s. If the speed of sound is 330 ms^-1, then the distance d between X and Y is ________.


A160 m
B270 m
C290 m
D320 m

Refer to the given dichotomous key. Identify P-T and select the correct statement regarding them.
I. (A) It is a unicellular organism. - Go to II
(B) It is a multicellular organism. - Go to IV
II. (A) It possesses well organised nucleus. - Go to III
(B) It lacks well organised nucleus. -
III. (A) Nutrition is parasitic. -
(B) Nutrition is mixotrophic. -
IV. (A) It possesses chlorophyll. -
(B) It lacks chlorophyll. -

AP could be slipper animalcule.
BR could be Euglena which possesses cilia that help in movement.
CQ could be Plasmodium which causes malaria or it could be Entamoeba which causes amoebic dysentery in humans.
DS could be an alga like Chlamydomonas whereas T could be a scavenger like vulture or a decomposer like Giardia.

Select the plant which is of the same type as shown in the picture.


ACoriander
BMango
CBanana
DMint

In the above box, which animal is a prey?

ASquirrel
BSnake
CHawk
DBoth a and b

During the science activity, class teacher arranged the test tubes as shown in the figure and asked students to predict the effect of various indicators on the given solutions.


Which of the following statements are correct?
I. Turmeric solution will turn red in test tubes 1 and 4.
II. Methyl orange will turn yellow in test tubes 1 and 3.
III. China rose indicator will turn dark pink in test tube 2.
IV. Blue litmus solution will turn red in test tubes 1 and 4.

AI and IV only
BI, II and IV only
CII and III only
DNone of these

Padma conducted an experiment as shown below by using different materials.


Padma pulled on the spring balance until the material was separated from the magnet. The readings on the spring balance were recorded as shown in the table below.



What conclusions could Padma make from her experiment?
(i) Soft iron needs the largest force in order to be separated from a magnet.
(ii) Nickel is most easily magnetised while soft iron is least easily magnetised.
(iii) Nickel and cobalt are non-magnetic materials.
(iv) Steel makes the strongest permanent magnet.

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