The S refers to sterling silver, and the 115 refers to the ring being 11.5% sterling. The triangle and TD are very likely a maker's mark.
The Pythagorean Theorem: a^2+b^2=c^2, for checking squareness, a critical rule in carpentry. If two adjacent and perpendicular walls in a room are legs of a triangle, points a and b can be marked on each leg respectively and hypotenuse c measured with a tape measure (c) to confirm squareness or degree out of square. This can be used in many applications from framing to tiling. Most carpenters I've met use the 3-4-5 rule and don't even know what it's called!
Sin or Sine is the ratio of the Opposite side Over The Hypoteneuse of any right angled triangle inverse sin or inverse sine ( they mean the same thing ) uses the same ratio to find an unknown angle and can be written as sin-1 so if you know two sides ( opposite and Hypoteneuse ) then you can work out the sin...then you can either use a calculator to determine the inverse ( or angle ) or you could look up the sin in a booklet of sin values and determine the angle Example : in the triangle ABC the line ab=4 ac = 5 and the angle abc =90 we could find the sin of the angle acb sinacb= opp/hyp = 4/5 = 0.8 to find sin-1 of 0.8 calcultor press 0.8 press inv button or on newer calculators the 2nd functon button then press the button marked sin the display should then display 53.1301....or 53 to 2 sig figures
It's possible that either the angles or sides are labeled according to length or size.
A tool used for measuring angles is called a protractor. It typically has a semicircular or circular shape marked with degrees from 0 to 180 or 0 to 360, allowing users to measure both acute and obtuse angles accurately. Protractors are commonly used in geometry, drafting, and various engineering applications. They can be made of plastic, metal, or wood, and some digital versions are also available for enhanced precision.
A trigonometrical station is a fixed point on the Earth's surface used for triangulation in surveying and geodesy. These stations are equipped with precise instruments to measure angles and distances to other stations, enabling the accurate mapping of the terrain. They are essential for creating topographical maps and for various applications in fields like construction, navigation, and land development. Typically, trigonometrical stations are marked and maintained to ensure their reliability for long-term measurements.
The German Triangle is marked by three cities: Cincinnati, Milwaikee, and St. Louis
The Triangle Shirtwaist Fire
In that triangle, one of the angles must be a right angle, and another one of the angles must be marked with or the measurement of the angle. Tangent is the ratio of opposite side over adjacent side. The opposite and adjacent sides are determined by the position of the marked angle.
It's 30o, no hang on, it's 28o...wait a minute, it's 57o. Hmmm...looks like my psychic abilities are failing me again: without the DIAGRAM I can't work it out (not can anyone else).
Qgt
Yes,it was made by bii int. For the 39, 59 and model 52they are super rare to find and are marked 39-ss with a triangle logo with the bii inside
4 karrot gold
If a package of tofutti pops is marked as having 12 pops inside, the box should contain 12 pops. If there were only 11 tofutti pops inside the box, it is likely that there was a packaging error.
Are labeled and the locations marked on the inside of the fuse box cover. The lighter fuse will be marked in the diagram.
The letter "J" in a triangle crown, along with the letter "F" marked with "EP-11s," likely refers to a specific brand or logo, possibly associated with a jewelry or design company. The triangle crown could symbolize quality or luxury, while "EP-11s" might denote a product model or series. However, without more context, it's challenging to determine the exact significance of these symbols.
Made by Robert Leekya
It is the key marked " Caps Lock."