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).
Definition of Line of Symmetry. Line of symmetry is a line that divides a figure into two congruent parts, each of which is the mirror images of the other. When the figure having a line of symmetry is folded along the line of symmetry, the two parts should coincide.