1. What is the product made of : PLA, also known as polylactic acid, is a polyester made through the fermentation under controlled conditions of a carbohydrate source like corn starch, tapioca roots, or sugarcane. Plants  → sugar →fermentation（lactic acid）→monomer production (lactide)→polymer production→PLA→polumer conversion→sheet of PLA for packaging or PLA for fibers etc.   2.&nb...