Protractor on the dial from 180°, as the dial is graduated from opposite zero marks to 90° each way. Since the spaces, both on the main scale and the Vernier scale, are numbered both to the right and to the left from zero, any angle can be measured. The readings can be taken either to the right or to the left, according to the direction in which the zero on the main scale is moved. Reading the Vernier scale: The bevel protractor Vernier scale may have graduations of 5′ (minutes) or 1/12°. Each space on the Vernier scale is 5′ less
Circular triangle are zero. The arbelos is a special case with three collinear vertices and three semicircular edges. Other circular triangles can have a mixture of convex and concave circular arc edges. Long arcs can produce concave figures regardless of whether individual edges are curved inwards or outwards. Inward curved arcs can create self-intersecting forms, such as the a triquetra figure: Circular triangles can be seen in tessellation. Circular triangle In geometry, a circular triangle is a triangle with circular arc edges. A convex circular triangle may be constructed by three circles intersecting each other and represents the area of intersection. Its