$9.$ Find out if the statement is true or false: Polymerization is a refining technique that combines smaller molecules like propylene or butylene into larger, more complex molecules, typically using a catalyst under moderate temperature conditions to produce lubricants and waxes.

$10.$ Find out if the statement is true or false: Isomerization is a process that not only rearranges hydrocarbons to form more useful isomers but also significantly reduces the freezing point of jet fuels, making them more efficient in colder climates.

$11.$ Find out if the statement is true or false: Naphtha, a light hydrocarbon mixture derived from crude oil, is primarily used as a solvent in industrial cleaning and as a base component for petrochemical synthesis, including plastics and synthetic rubber.

$12.$ Find out if the statement is true or false: Aviation gasoline, used in turbine engines, requires additives such as tetraethyl lead to increase its octane rating and prevent engine knocking during high$-$altitude flights.