4b) visual observations as the sample is brought near the side of the flame, in the flame, and out of the flame, 4c) odor as the fibres burn, 4d) characteristics of the ash including the colour and texture. 4e) The man-made fibers will decompose and melt. much quicker than either the animal or vegetable fibers.
Bluefin tuna swim in a holding pen in Australia. A conservation group has named three fish species that it says are at risk of extinction. The fish are threatened because of overfishing to meet the worldâs growing demand for food.
The nonprofit Food & Water Watch looked at all the varieties of fish out there, how they were harvested, how certain species are farmed and levels of toxic contaminants like mercury or PCBs in the fish, as well as how heavily local fishermen relied upon fisheries for their economic survival.