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
OMB Circular A-16 OMB Circular A-16 OMB Circular A-16, revised August 19, 2002, is a Government circular that was created by the United States Office of Management and Budget (OMB) to provide guidance for federal agencies that create, maintain or use spatial data directly or indirectly through the establishment of the National Spatial Data Infrastructure (NSDI) and the Federal Geographic Data Committee (FGDC). The circular establishes guidelines for the management of digital spatial data and the use of those assets. It also appoints the FGDC to the interagency coordinating body for NSDI-related activities. The Secretary of the Interior is established as chair, with