Prove that an angle subtended at the circumference of a circle by any diameter is a right-angle.

What is the circumference of a circle of diameter 10 cm (Take pi = 3.14)?

Draw any circle and mark: a diameter

Prove that angle in a semi-circle is right angle.

Fill in the Blanks: Angles subtended by an arc at the centre of a circle is _______ the angle subtended by the same arc at any other point on the remaining part of the circle.

Sum of the four angles of a quadrilateral is the four right angles.

Show that each angle of a rectangle is a right angle.

Prove that the angle in a segment smaller than a semi-cricle is greater than a right angle.