Answer:
B. Aerobic bottom water
D. High organic productivity in the overlying oxygen rich water
Explanation:
A Shale is a sedimentary rock usually formed from silt and clay-size mineral. There are different colors of Shale. The Black Shale is formed under anaerobic conditions. This means that oxygen is deficient in the water where the Shale forms.
A little amount of organic materials is required for the formation of Black Shale and because Black Shale is formed in an environment lacking oxygen, an oxygen-rich water would not be necessary for its growth. Sediments are necessary in the formation of Black Shale.
The United States is an example of Democracy.
Answer:
between 25 and 40 degrees
Explanation:
Answer: B. Glaciers are thick sheets of recrystallized ice.
D. Glaciers last throughout the year.
Explanation:
A glacier is a continuously moving ice mass. It is formed over many years in regions where snow falls more quickly than it melts and evaporates. They are not stationary, but move due to their weight.
A high number of glaciers exist in mountainous regions but glaciers are not limited to these areas. They also do form on land.
Glaciers currently cover about 10% of our planet, down from the last Ice age when 32% of land was covered in ice.
