The Federal Aviation Administration (FAA) shares the Environmental Protection Agency's (EPA) concerns about lead emissions from small aircraft. Owners and operators of more than 200,000 piston-engine aircraft operating in the United States rely on aviation gasoline (avgas) to power their aircraft.
Symmetry (noun). a due proportion of the several parts of a body to each other; adaptation of the form or dimensions of the several parts of a thing to each other; the union and conformity of the members of a work to the whole. Symmetry (noun).
radial symmetry. n. 1. (Biology) a type of structure of an organism or part of an organism in which a vertical cut through the axis in any of two or more planes produces two halves that are mirror images of each other. Compare bilateral symmetry.oun. 1. radial symmetry-the property of symmetry about an axis; the starfish illustrates radial symmetry. symmetricalness, symmetry, correspondence, balance - (mathematics) an attribute of a shape or relation; exact reflection of form on opposite sides of a dividing line or plane.