Cyanobacteria, also known as "blue-green algae", are the unicellular organisms which are able to produce oxygen.
Approximately 540 years ago, the atmosphere was very poor on oxygen. Cyanobacteria are thought to be responsible for the oxidization of the atmosphere back then, in an event known as <em>"The Great Oxygenation Event"</em>. As a result, Earth's life forms suffered drastic changes in their composition, as they evolved from being <em>anaerobic</em> to becoming organisms <em>highly dependant</em> on oxygen. The oxygenation of the atmosphere would eventually provide the adequate environment in order for the <em>Cambrian Explosion</em>, or the first diversification of living organisms, to happen.
Your answer is C, during the Great Depression the rate of unemployment was at a high of 25.6%
Im writing this to finish a challenge
A dissenting opinion disagrees with the majority because of the reasoning and/or the principles of law on which the decision is based. A concurring opinion agrees with the end result of the court but offers further comment possibly because they disagree with how the court reached its conclusion.
D I'm not as sure about this question I'm just guessing