Squaring the circle: the areas of this square and this circle are both equal to Ï. In 1882, it was proven that this figure cannot be constructed in a finite number of steps with an idealized compass and straightedge.
Not to be confused with Cloud top. In aviation, ceiling is a measurement of the cloud base height relative to the ground. Ceiling is reported as part of the METAR (METeorological Aviation Report) used for flight planning by pilots worldwide. A ceiling listed as unlimited means either that the sky is mostly free of cloud cover, or that the cloud is high enough not to impede Visual Flight Rules (VFR) operation. In a METAR, the lowest BKN or OVC layer specifies the cloud ceiling.
constriction beams is a generic term, joists are the studs in the ceiling (walls=studs/ceiling-joists) and, I assume, you mean headers. headers are the supports over openings-doors,windows,archways, etc.