It is genetic - in my family there is no history of it as it is a recessive gene but my mum and dad were both carriers. In Scotland up to 13% of the population has red hair, but around 40% of the population is thought to carry the recessive gene responsible for the world's rarest natural hair colour.
On the other hand, synthetic base oil molecules are chemically controlled, which provides increased ï¬ lm strength and lubricity over petroleum oils. The performance qualities of base oils have a marked impact on the performance qualities of the ï¬ nished product.
-- Corie. TOM: The main difference is that in diesel fuel, you can still see the dinosaur bones floating around. RAY: Actually, gasoline and diesel fuel both are products that are made from crude oil. When a barrel of crude oil comes into the refinery, it's distilled into its heavier and lighter components.