$1.$ Find out if the statement is true or false: Petroleum, commonly referred to as crude oil, is a naturally occurring liquid found in geological formations beneath the Earth's surface, primarily composed of hydrocarbons and other organic compounds, and is primarily used as a fuel source for transportation and heating.

$2.$ Find out if the statement is true or false: The majority of the world's petroleum reserves are concentrated in the Middle East, Venezuela, and Russia, which collectively hold over $75\%$ of the global reserves, significantly influencing global oil prices and energy politics.

$3.$ Find out if the statement is true or false: Petroleum crude oil can be classified into three main types based on its API gravity and sulfur content: light, medium, and heavy; and sweet or sour, respectively, affecting its market price and refining requirements.

$4.$ Find out if the statement is true or false: Thermal cracking, an important process in the refining of crude oil, utilizes extreme heat and pressure to break down larger, heavier hydrocarbon molecules into smaller, more valuable ones like gasoline and kerosene without the use of catalysts.