Angle ∠BAC might refer to any of four angles: the clockwise angle from B to C, the anticlockwise angle from B to C, the clockwise angle from C to B, or the anticlockwise angle from C to B, where the direction in which the angle is measured determines its sign (see Positive and negative angles). However, in many geometrical situations it is obvious from context that the positive angle less than or equal to 180 degrees is meant, and no ambiguity arises. Otherwise, a convention may be adopted so that ∠BAC always refers to the anticlockwise (positive) angle from B to
Type 90 Ship-to-Ship Missile Type 90 Ship-to-Ship Missile The Type 90 Ship-to-Ship Missile (90式艦対艦誘導弾, SSM-1B) is a ship-launched anti-ship missile developed by Japan's Mitsubishi Heavy Industries that entered service in 1992. It is a naval version of the truck-launched Type 88 (SSM-1) missile, which in turn was developed from the air-launched Type 80 (ASM-1) missile. The Japan Maritime Self-Defense Force bought 384 of the missiles which it fitted to its "Akizuki", "Takanami", Hayabusa, and "Murasame"-class ships. With a range of , high subsonic speed and warhead, the Type 90 is similar to the US's RGM-84 Harpoon missile, and is replacing Harpoon on Japanese ships.