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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.

Refer to the given dichotomous key and identify P, Q, R, S and T.
I. (A) Propagates vegetatively by natural methods. - Go to II
(B) Propagates vegetatively by artificial methods. - Go to IV
II. (A) New plant develops from stem of parent plant. - Go to III
(B) Roots of parent plant gives rise to new plant. - P
III. (A) Short underground stem covered with fleshy scale leaves. - Q
(B) Modified underground stems (bearing buds) which store food and become swollen. - R
IV. (A) Roots develop from young branch bent towards the ground and covered with soil. - S
(B) It involves placing of stem cutting of one plant over cut stem (having extensive roots) of other plant and tying them. - T

AP could be potato whereas R could be garlic.
BT could be coriander whereas S could be spinach.
CP could be beetroot whereas Q could be turnip.
DQ could be onion whereas S could be strawberry.

Refer to the given Venn diagram and select the correct option regarding P and Q.


AAngora, Mohair and cashmere are few varieties of P obtained from different mammals.
BP and Q when burnt give the smell of burning hair and charred meat respectively.
CFabric made of P can be used in winter clothing whereas fabric made of Q is waterproof hence can be used for making umbrellas or raincoats.
DReeling is involved in processing of P whereas fibre Q is obtained by retting.

Read the given paragraph and select the option that correctly fills the blanks in it. The female silk (i) lays egg which hatches into a tiny caterpillar. It feeds on (ii) and grows. When it is ready to enter the next stage in its life cycle, it first weaves a net to hold itself by secreting a proteinaceous fibre which (iii) on exposure to air. This is the silk fibre. The silkworm covers itself completely with this fibre to form a (iv) . At this stage, the larva is called a (v).
(i)-----(ii)-----(iii)-----(iv)-----(v)

AMoth---Seeds---Hardens---Pupa---Cocoon
BLarva---Leaves---Softens---Pupa---Cocoon
CLarva---Leaves---Softens---Pupa---Cocoon
DMoth---Stem---Softens---Cocoon---Pupa

A few processes are listed in the table :

Select the correct option.

A (i) and (iv) are examples of rapid combustion.
B (v) is an example of slow combustion.
C (iii) and (iv) are examples of spontaneous combustion.
D (i) and (ii) are examples of slow combustion.

Observe the given figure of a candle flame and select the incorrect statement regarding X, Y and Z.


AWax vapours burn completely in zone Y which is yellow in colour.
BTemperature in zone Z is about 800-1000 °C.
CPlenty of oxygen is available in zone X.
DNone of these

Match the columns and select the correct option.


A a - 2, b - 3, c - 4, d - 5, e - 6
B a - 1, b - 3, c - 6, d - 2, e - 5
C a - 3, b - 6, c - 4, d - 5, e - 2
D a - 1, b - 3, c - 4, d - 2, e - 6

Six equal resistances are connected between points P, Q and R as shown in the figure. The net resistance will be maximum between


A P and Q
B Q and R
C P and R
D Any two points.

Electricity travelling through a wire is an example of

A A force applied by a simple machine
B Energy flowing through the water cycle
C Earth's gravitational pull on an object
D Energy being transferred from place to place.