5. The atmosphere of early Earth is unlike today's atmosphere. A. When did oxygen first appear in Earth's early atmosphere? (3 points)

B. What factor caused the appearance of oxygen? (3 points)

C. What is one form of evidence used to support this theory? (4 points)

Acar traveld with an average speed of 60 miles per hour for 2 hours. how far did it travel

The unique structure of the neuron is dedicated to the efficient and rapid transmission of neural signals. the relationship between neurons, the spinal cord, and the brain constitutes an elaborate communication system throughout the human body. all but one of the functions listed below are a result of this interaction.

The table presents the average day and night temperatures in five cities. it also reveals whether a city receives substantial rainfall (wet climate) or little rainfall (dry climate). which city’s rocks are likeliest to experience frost wedging, and why? a) city a because the consistently subzero temperature would prevent water from melting b) city b because it is a wet region and the temperature fluctuates around the freezing point c) city c because it receives plenty of rain fall and the weather is moderately cool d) city d because the hot and dry weather would cause rocks to absorb water