Dipropylene glycol methyl ether (DPGME) is one of the most commonly used propylene glycol ethers in industry and is discussed in a recently published NEG/NIOSH document. DPGME is a collective term describing a mixture of structural isomers.
The Incas were a civilization in South America formed by ethnic Quechua people also known as Amerindians. In 1400AD they were a small highland tribe, one hundred years later in the early 16th century the Incas rose to conquer and control the largest empire ever seen in the Americas forming the great Inca Empire.
Quick Answer. The Incas' social structure was divided into four levels: Sapa Inca, royalty, nobility and the ayllu. The Sapa Inca was the most powerful person in the entire empire; he served as the king of the Incas and was believed to be the son of the sun.. Continue Reading.