Ключевые слова: accuracy, background, bar, calibration, centimeter, chart, concept, design, distance, education, element, equipment, flat, geometric, geometry, graphic, horizontal, icon, illustration, inch, indicator, instrument, isolated, length, level, line, lines, long, measure, measurement, measuring, meter, millimeter, number, object, office, precision, ruler, scale, school, sign, size, symbol, tape, tool, unit, units,