What are the four primary elements found in coal? 90% carbon, 3% oxygen, 4% hydrogen, and 1% sulfur. What forms of air pollution do these elements become as part of coal combustion? When coal is burned for fuel, it combines with oxygen in air to form several air pollutions. What substances are contained within coal ash?
It is an oil painting on canvas.   It is to show Picasso's anger at the bombing of the little Spanish town Guernica in 1937.  .
The painting is believed to be a response to the bombing of Guernica, a Basque Country village in northern Spain, by German and Italian warplanes at the request of the Spanish Nationalists.