Energy from a source that is not depleted when used, such as wind or solar power.
Answer:
The marshes are defined as the type of wetland where the water covers the ground surface for a long period of time. Here, the trees are absent and are mostly dominated by the grasses and other small herbivore plants. They are commonly formed in delta type of environment where the rivers adds water into the seas. It forms an isolated and distinct ecosystem.
The marshes in nature, behaves like a filtration process as the vegetation that are present in marshes takes up more amount of nutrients for their growth and expansion. But, if it does not use up these excess nutrients then it cause water pollution comprising of nitrogen and phosphorous.
They also plays an important role in the reduction of damages that are caused by a flood.
The marshes are sometimes seasonal and it occurs when the height of the river level is relatively high, and it floods the grassland areas.
The marshes are of three types-
(1) Tidal salt marshes
(2) Tidal freshwater marshes
(3) Inland freshwater marshes.
The population of Oregon which is given above may also be expressed in scientific notation as,
4 x 10^6
The magnitude of this number is the exponent of 10 in the scientific notation. Thus, the answer is letter "B. 6".
Earth is composed of four main layers, starting with an inner core at the planet's center, enveloped by the outer core, mantle, and crust. The inner core is a solid sphere made of iron and nickel metals about 759 miles (1,221 kilometers) in radius.
source: nasa