The word that best fits in the blank in the sentence, "The first major source of oxygen gas was " is cyanobacteria. Thus, the answer is letter C. Cyanobacteria are blue-green algae and they are believed to have caused the "great Oxidation Event".
Answer from: Quest
shield volcanos are angry and get mad over the smallest things so much that there heads erupt pahoehoe and a'a lava. a composite volcano is the poller opposite of a shield volcano. its peaceful thing and knows how to control its emotions.
Answer from: Quest
The phase where ice changes directly to gas is called sublimation
Another question on Chemistry
Chemistry, 22.06.2019 09:00
At 300 mm hg, a gas has a volume of 380 l, what is the volume at standard pressure
In a heat of an engine, if 700 j enters the system, and the piston does 400 j of work what is the final internal (thermal) energy of the system if the initial energy is 1,500 j