Right angle Right angle In geometry and trigonometry, a right angle is an angle of exactly 90° (degrees), corresponding to a quarter turn. If a ray is placed so that its endpoint is on a line and the adjacent angles are equal, then they are right angles. The term is a calque of Latin "angulus rectus"; here "rectus" means "upright", referring to the vertical perpendicular to a horizontal base line. Closely related and important geometrical concepts are perpendicular lines, meaning lines that form right angles at their point of intersection, and orthogonality, which is the property of forming right angles, usually applied
Type 90 Kyū-maru kW (1,500 horsepower). The hydropneumatic suspension units are mounted on the front and rear pair of road wheels, which can be adjusted on-the-fly to deal with uneven terrain, a requirement on Japan's rough, mountainous terrain. According to the Japanese Ministry of Defense official data report, the acceleration of the type is 0–200 m in 20 seconds. The Type 90 has an approximate unit cost of 790 million Japanese yen or approximately 7.4 million US dollars at 2008 exchange rates. 341 Type 90 tanks were produced between 1990 and 2009 with an average annual production number of 19 vehicles. The original