$5.$ Find out if the statement is true or false: Catalytic cracking, unlike thermal cracking, requires the presence of a catalyst, typically a form of acidic silica$-$alumina, which helps lower the temperature needed for the cracking reaction, thereby conserving energy and reducing carbon emissions.

$6.$ Find out if the statement is true or false: Hydrocracking is a versatile refining process that not only breaks down large hydrocarbon molecules into smaller ones but also removes sulfur and nitrogen impurities using hydrogen gas under high temperatures and pressures.

$7.$ Find out if the statement is true or false: Reforming processes, both thermal and catalytic, are primarily aimed at increasing the octane number of gasoline. Catalytic reforming, however, also contributes to the production of hydrogen gas used in other refining processes like hydrocracking.

$8.$ Find out if the statement is true or false: Alkylation in petroleum refining is a process where isobutane is combined with olefins in the presence of a strong acid such as sulfuric acid or hydrofluoric acid, resulting in high$-$octane blending components for gasoline.