Answer:Nicholas Steno first formulated the principles that allow scientists to determine the relative ages of rocks in the 17th century. Steno stated that sedimentary rocks are formed in continuous, horizontal layers, with younger layers on top of older layers.
Explanation:
Between the 1870 and 1900
I think B but I might be ! wrong !
Answer:
Based on the solar light that enters the oceans and river
Explanation:
- River ecosystem of a couple of both biotic and abiotic components among the plants and animals involving there physical and chemical properties. As the flow of water is unidirectional, it's in state of continuous physical change and has a high degree of spatial and temporal heterogeneity.
- River sources are small, and in the areas of mountain streams, are steep and erosional. In temperate environments, overhead tree canopy conditions result in cool, well-oxygenated streams.
- All sorts of communities like coastal, estuaries, reefs and deep-sea trenches like Mariana trench which has no sunlight has a distinct type of community.
Answer:
The darkest time of year at the North Pole is the Winter Solstice, approximately December 21. There has been no sunlight or even twilight since early October. The darkness lasts until the beginning of dawn in early March.