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Read the given statements and select the option which correctly fills the blanks.
(i) Natural disaster caused by earthquakes or volcanic eruptions under the sea and oceans is called 1.
(ii) Rainwater harvesting is used to minimize the effects of 2.
(iii) 3 is a tropical storm, characterised by fast spinning winds.

X is the fourth layer of the atmosphere, it extends from 80 km to 500 km above the earth's surface and space shuttles orbit in this layer. X is

ATroposphere
BStratosphere
CMesosphere
DThermosphere.

Which of the following statements is incorrect?

A Linen is obtained from plants and absorbs well.
B Plastic conducts electricity very well.
C Evaporation is faster when the surface area is larger.
D Copper vessels lose their shine over time due to action of air and moisture on them.

Select the incorrect statements.
I. In railway tracks, space is left between two rails at the joint to allow for the expansion of iron rails during winter.
II. For gases, solubility in water decreases with rise in temperature.
III. When mercury thermometer is used to measure the temperature, a chemical change takes place.
IV. At a particular temperature, the amount of salt or sugar that can be dissolved in 100 mL of water is same.
V. Galvanisation involves a physical change.

A I and II only
B III and V only
C I, III, IV and V only
D I, II, III, IV and V

Refer to the given flow chart and select the correct statement regarding it.


ADeficiency of P could cause marasmus whereas deficiency of Q could cause night blindness.
BR could help in proper functioning of nerves and muscles whereas S could be found in blood that neutralises the effects of bacteria and viruses.
CQ could help in red blood cell production whereas R could help in calcium absorption.
DP could get stored in the body cells as glycogen whereas deficiency of Q could cause pellagra.

A concave mirror is used to form a real image of a candle. If the upper half of the mirror is covered by a piece of paper, then

A The image becomes dimmer
B The image becomes brighter
C The image remains same
D Both a and b

Which of the following statements is true about prime numbers?

A There are finite number of prime numbers.
B Every prime number is odd.
C There is no largest prime number.
D A whole number is either prime or it can be expressed as a product of primes.

Identify W, X, Y and Z.
W : An edible liquid miscible in water
X : A non-edible, inflammable liquid that floats on water
Y : An edible, coloured liquid that does not flow easily
Z : A colourless, non-inflammable liquid

Which of the following is not a behavioural adaptation?

AA hognose snake plays dead when it feels threatened.
BA Siberian crane migrates from West Siberia to India to escape extreme cold.
CWestern swamp turtle aestivates to escape excessive hot condition.
DLeaf insect mimics/resembles a green or a dry leaf to escape its predators.

Consider the following statements and select the correct option which correctly identifies true (T) and false (F).
(i) Iron loses its magnetism easily.
(ii) Steel is a hard magnetic material.
(iii) Iron is used to make permanent magnet.
(iv) Steel is used to make electromagnet.