Answer:
Formaldehyde can be added as a preservative to food, but it can also be produced as the result of cooking and smoking. Formaldehyde also occurs naturally in the environment. Humans and most other living organisms make small amounts as part of normal metabolic processes. Formaldehyde is also a byproduct of combustion. When burning natural gas, kerosene, gasoline, wood, or tobacco, formaldehyde is produced. Automobile exhaust is a common source of formaldehyde in our environment. Tobacco smoking in the home is another source of the chemical in the indoor environment.
Explanation:
Because its an everyday thing. Its not something new
<span>The major centers of
knowledge and learning i</span>n Western Europe during 6th and 7th centuries were located in monasteries.
After the fall of the Roman Empire (during the Dark Ages), the monasteries were
used to preserve the medical writings and books of the Greeks and Romans. Until
universities such as Salemo were built, the monasteries were the only centers
of learning.
