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3.PQRS is a quadrilateral in which PQ = QR = RS = SP, PR = SQ. All angles,  P,  Q,  R and  S are equal and   CUBOID
 the diagonals bisect each other at right angles. Name the quadrilateral.
        CUBOID Solids such as a wooden box, a matchbox, a brick, a book, an almirah, etc., are all in the shape of a
 4.ABCD is a kite. Draw the figure and name the equal sides. Draw the diagonals AC and BD and let them meet at   cuboid.
 0. Is  AOD =  AOB? What is the measure of  AOD and  AOB?  Some of these shapes are given below.

 5. ABCD is a quadrilateral. AB = CD and AD = BC. All interior angles are equal to 90’. AC = BD. Name
 the quadrilateral.

 6. Distinguish between the following:
    a. a square and a rectangle.
    b. a square and a rhombus.
    c. a trapezium and an isosceles trapezium.
        A cuboid has length, breadth and height.
 7. Write the names of the polygons with the following number of sides:  Various parts of a cuboid are given below

    a. six     b. eight    c. ten     d. twelve      e. four  (i) FACES A cuboid has stx rectangular faces.
        The opposite faces of a cuboid are identical.
 8. A pentagon has sides measuring 5 cm, 6 cm, 7 cm, 5 cm and 10 cm. Is it a regular polygon? Give reasons.

 9.In the parallelogram PQRS, _P is double of _Q. Find all the angles of the parallelogram.  (ii) EDGES Too adjacent faces of a cuboid meet in a line segment,
        called an edge of the cuboid. A cuboid has 12 edges.
 10. In the given figure, name the different polygons labelled as
        (iii) VERTICES Three edges of a cuboid meet at a point, called a vertex.
    a.    ABC     b.    PQRS  A cuboid has 8 vertices.
 c.  MQRN  d.  AMSC
    e.    MQCS  Thus, a cuboid has 6 rectangular faces, 12 edges and 8 vertices.





                                                           CUBE
 THREE-DIMENSIONAL SHAPES
        CUBE A cuboid whose length, breadth and height are equal is called a cube.
 CUBOID, CUBE, CYLINDER, SPHERE, CONE, PRISM AND PYRAMID
 IDEA OF SPACE When we look at something empty, like a box, room or bowl, it has space. We can keep things
 in that space. A park has space for us to play.  EXAMPLES Ice cubes, sugar cubes, dice, etc., are all examples of a cube.
 SOLID An object that has a fixed shape and size is called a solid. A solid occupies a fixed amount of space.  Clearly, a cube has 6 square faces, 12 edges and 8 vertices.
 Solids occur in different shapes.
 These shapes are known as three-dimensional shapes. The various types of these shapes are shown below.


                                                        CYLINDER


        CYLINDER Objects such as a circular pillar, a circular pipe, a test tube, a circular storage tank,
        a measuring jar, a gas cylinder, a circular powder ttn, etc., are in the shape of a cylinder.


        Some of these shapes are shown below.
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