Ключевые слова: accurate, angle, arc, background, black, cell, circle, clipart, curve, degree, design, device, divided, drafting, drawing, education, engineer, engineering, equipment, geometrical, geometry, grid, illustration, inch, instrument, isolated, line, math, mathematical, mathematics, measure, measurement, object, office, plan, plastic, protractor, ruler, school, semicircle, shadow, shape, sheet, single, tool, white, work,