Ключевые слова: accuracy, angle, background, black, centimeter, centimeters, chalkboard, closeup, college, color, copy, design, drafting, drawing, education, engineering, equipment, geometry, instrument, item, knowledge, learn, learning, length, line, markings, math, mathematical, mathematics, measurement, measuring, millimeter, number, object, one, orange, precision, ruler, school, science, shape, space, stationery, study, supply, text, top, triangle, university, view,