18) What is the type of triangle if the sides of a triangle are unequal?

19) Which drawing instrument is used to draw circles and arcs?

20) What is the distance from the centre to any point on the circle?

21) What is the part of a circle with horizontal and vertical radii making 90 Degree to each other?

22) What is the term for a quadrilateral whose all four sides are equal and its four angles are right angles?