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Read the given statements and select the correct option.
Statement 1 : Animals cannot take nitrogen directly from atmosphere rather they obtain it from plants they eat.
Statement 2 : Plants also cannot take nitrogen directly from atmosphere, rather free living or symbiotic nitrogen fixing bacteria present in soil convert atmospheric nitrogen into soluble nitrogen compounds that can be used by plants.

ABoth statements 1 and 2 are true and statement 2 is the correct explanation of statement 1.
BBoth statements 1 and 2 are true but statement 2 is not the correct explanation of statement 1.
CStatement 1 is true but statement 2 is false.
DBoth statements 1 and 2 are false.

A body projected vertically from the surface of the earth, reaches a height equal to earth's radius before returning to the earth. The power exerted by the gravitational force

AIs greatest at the highest position of the body
BIs greatest at the instant just before the body hits the earth
CRemains constant throughout the motion
DNone of these.

In a village, farmers started using DDT as pesticide in their crop fields, located nearby river. Given table shows the concentration of DDT as found in tissues of various organisms present in that river.

Which of the following option shows the correct order in which these organisms are linked in a food chain?

AI → III → V → II → IV
BI → V → III → II → IV
CIV → II → III → V → I
DII → IV → V → III → I

Study the given table and fill in the blanks by selecting an appropriate option.

(i)-----(ii)-----(iii)-----(iv)

ASilver nitrate---Carbonic acid---Hydrochloric acid---Ammonium nitrate
BSodium nitrate---Hydrochloric acid---Carbonic acid---Silver nitrate
CPotashalum---Sulphuric acid---Nitric acid---Sodium nitrate
DAmmonium nitrate---Carbonic acid---Sulphuric acid---Silver nitrate

Mayank set-up an experiment as shown below.

Which of the following graphs correctly represents the changes in weights of Visking tubings P and Q?

A
B
C
D

Nutrient 'X' keeps teeth and bones healthy. It is present in orange and amla. Deficiency of 'X' results in bleeding gums.
Select the option that correctly identifies 'X'.

A Vitamin C
B Calcium
C Vitamin K
D Carbohydrate

There are four electromagnets as shown in the figure.

Which one of following options is correct regarding strength of electromagnets?

AI = II < III < IV
BI > II > III = IV
CI < II < III = IV
DNone of these

An electron jumps from an orbit P to Q and loses energy. The same electron when jumps from R to Q, gains energy.
The increasing order of distance of these orbits from the nucleus is

A P < Q < R
B R < P < Q
C R < Q < P
D P < R < Q

A brief information about two atoms X and Y is given:
X : Atomic number = 7, Mass number = 14
Y : Atomic number = 7, Mass number = 15
Which of the following is correct about these two atoms?

A Electronic configuration of X is 2, 8, 4 while that of Y is 2, 8, 5.
B Both X and Y contain 7 neutrons.
C X has 2 electron shells while Y has 3 electron shells.
D Both X and Y have 5 valence electrons.

‘R’ is the fifth planet from the Sun. Which of the following is correct regarding R?

A It is known as red planet.
B It has lowest number of Moons.
C It is the largest planet .
D It has a ring around itself.