Your first stop should be a libary, since it would really help if you knew what you were talking about.

Biodiesel is not a "gasoline alternative." It is a diesel alternative. ASTM-certified biodiesel will work in any diesel engine. It will not work in any gasoline engine. (Owners of diesel vehicles still under warranty should consult their vehicle manufacturer before using biodiesel.)

Biodiesel is not "made from a mixture of diesel gasoline and vegetable oil." And there's no such thing as "diesel gasoline." Like diesel and gasoline, biodiesel is a hydrocarbon fuel. Unlike diesel and gasoline, it is not made from petroleum.

Vegetable oil may be nontoxic and biodegradable. Biodiesel may be biodegradable, but it should not be considered nontoxic.

Compressed natural gas is not a "green" fuel; it is a fossil fuel. Ethanol and biodiesel may or may not be "green," depending on the feedstocks from which they are made. Corn-based ethanol is not "green." Algae-based biodiesel is "green."