Information: - A conventional fixed-wing aircraft flight control system consists of flight control surfaces, the respective cockpit controls, connecting linkages, and the necessary operating mechanisms to control an aircraft's direction in flight. Aircraft engine controls are also considered as flight controls as they change speed. - In automobiles, power steering (also power assisted steering (PAS) or steering assist system) helps drivers steer by augmenting steering effort of the steering wheel. - The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling mechanism to the braking mechanism. - Hydraulic machines are machinery and tools that use liquid fluid power to do simple work. Heavy equipment is a common example. - Garbage truck or dustcart refers to a truck specially designed to collect municipal solid waste and haul the collected waste to a solid waste treatment facility such as a landfill. Other common names for this type of truck include trash truck in the United States, and rubbish truck, bin wagon, dustbin lorry, bin lorry or bin van elsewhere. Technical names include waste collection vehicle and refuse collection vehicle. These trucks are a common sight in most urban areas. - Excavators are heavy construction equipment consisting of a boom , dipper , bucket and cab on a rotating platform known as the '' house '' . The house sits atop an undercarriage with tracks or wheels . They are a natural progression from the steam shovels and often mistakenly called power shovels . All movement and functions of a hydraulic excavator are accomplished through the use of hydraulic fluid , with hydraulic cylinders and hydraulic motors . Due to the linear actuation of hydraulic cylinders , their mode of operation is fundamentally different from cable - operated excavators which uses winches and steel ropes to accomplish the movements . - An oil is any neutral, nonpolar chemical substance that is a viscous liquid at ambient temperatures and is both hydrophobic (immiscible with water, literally "water fearing") and lipophilic (miscible with other oils, literally "fat loving"). Oils have a high carbon and hydrogen content and are usually flammable and surface active. - A backhoe, also called a rear actor or back actor, is a piece of excavating equipment or digger consisting of a digging bucket on the end of a two-part articulated arm. They are typically mounted on the back of a tractor or front loader, the latter forming a 'backhoe loader' ("colloquially known as a JCB in Ireland and UK"). The section of the arm closest to the vehicle is known as the boom, and the section which carries the bucket is known as the dipper or dipper-stick , terms derived from steam shovels). The boom is generally attached to the vehicle through a pivot known as the king-post, which allows the arm to pivot left and right, usually through a total of around 180200 degrees. - Water is a transparent and nearly colorless chemical substance that is the main constituent of Earth's streams, lakes, and oceans, and the fluids of most living organisms. Its chemical formula is HO, meaning that its molecule contains one oxygen and two hydrogen atoms, that are connected by covalent bonds. Water strictly refers to the liquid state of that substance, that prevails at standard ambient temperature and pressure; but it often refers also to its solid state (ice) or its gaseous state (steam or water vapor). It also occurs in nature as snow, glaciers, ice packs and icebergs, clouds, fog, dew, aquifers, and atmospheric humidity. - A mineral oil or paraffin oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum. - Hydraulic fluid(s), also called hydraulic liquid(s), are the medium by which power is transferred in hydraulic machinery. Common hydraulic fluids are based on mineral oil or water. Examples of equipment that might use hydraulic fluids include excavators and backhoes, hydraulic brakes, power steering systems, transmissions, garbage trucks, aircraft flight control systems, lifts, and industrial machinery. What object entity has the relation of 'instance of' with the subject 'excavator'? Choices: - aircraft - aircraft engine - bin - brake - change - chemical substance - construction - direction - engine - equipment - facility - fluid - formula - heavy equipment - higher alkanes - house - hydrogen - landfill - liquid - mineral - molecule - municipal solid waste - oil - state - system - trash - treatment - truck - two - van - vehicle - water - wing
The answer to this question is:
heavy equipment