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Each Option: 1 Mark
Given that:
Line l is perpendicular to line m.
a) We can clearly see from the above diagram that CE = 5-3= 2 units
Also, EG = 7-5 = 2 units
$\therefore$ CE = EG = 2 units
b)As we have seen above CE = EG
So, E is the mid-point of line CG.
$\therefore$ Line PE bisects CG.
c) We can see from the above figure that
BE = 5-2 = 5 units
HE = 8-5 = 3 units
$\therefore$ E is the mid-point of the line BH.
Also given that line m is perpendicular to the line l.
$\therefore$ PE is the perpendicular bisector of the line segment BH.
Also, we have seen above that PE is also the perpendicular bisector of line segment CG.
$\therefore$ The required line segments are BH and CG.

Answer: Option C. -> 300m 
:
C
If you cover 360${}^{\circ }$ of the track , the length covered = 400m
So,
For 180${}^{\circ }$, the length covered will be
$=\frac{1}{2}\left(400m\right)=200m$
For 90${}^{\circ }$, the length covered will be
$=\frac{1}{2}\left(200m\right)=100m$
$\therefore$ For 270${}^{\circ }$, the length covered = length covered for 180${}^{\circ }+$ length covered for 90${}^{\circ }$
$=200m+100m=300m$

Answer: Option C. -> Using a divider and a ruler 
:
C
We can't measure length using a compass. By guessing, the length measured will be lessaccurate. By using ruler we can measure, but the accuracy decreases if the angle at which it isviewedis not appropriate. By using the divider and a ruler, we can measure the length moreaccurately.

Answer: Option B. -> BC⊥CD 
:
B
If you draw the pathon a paper, you will find it similar to the figure below. We can see that $BC\perp CD$.

Answer: Option D. -> 1 and 3 
:
D
In a regular polygon, all the angles should be equal in measureand all the sides should be equal in length. This is true only for figures 1 and 3.

:
A rectangular prism is basically a cuboid. A cuboid has 6 faces and 12 edges.

Answer: Option A. -> Point C lies between A and B 
:
A
We can see that AC + CB = 4 cm + 9 cm = 13 cm = AB. So, C lies between A and B.

:
Definition: 1 Mark
Difference: 1 Mark
Each Point: 1 Mark
A line segment is a linewhich iscontained betweentwopoints. Thelengthof the linesegmentis fixed.
While a line hasno ends andit isdenotedwith an arrow at both theends.
a. In the given figure five points A, B, C, D, and E are marked.
b. In the given figure there are ten line segments AB, AD, AE, AC, BD, BE, BC, DE, DC and EC.

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Steps: 2 Marks
Answer: 1 Mark
Given that:
ABCD is a rectangle.
E and F are the mid-points of the lines ACand BDrespectively.
$\therefore$AE=BF=EC=FD
Also, AH=HB=CG=GD [ H is mid point of AB , G is midpoint of CD ]
$\angle$A,$\angle$B,$\angle$C and$\angle$D are right angles.
The four sides of rectangle formed i.e. EHFG will have equal dimensions.
$\therefore$The length of all their diagonals will also be same.
EH=HF=FG=EG
All sides of the quadrilateral are equal.
So either it will be a Rhombus or a Square.
But for both of these quadrilaterals, the diagonals intersect at a right angle.
The angle formed between the diagonals is a right angle.

:
Given that
Length of line AB = 7m
Length of line AC = 9m
Length of line BC = 2m
We can clearly see that the length of line AC > BC.
Also, AB + BC = AC
$\therefore$Point B lies between A and C.
AB + BC = AC.