Answer:
F Anthracite (the hardest coal)
Explanation:
Coal is a sedimentary rock that is formed from plant materials. These plant materials must have been trapped and compacted in an environment where they are not able decay. Such an environment is a swamp.
The first grade of coal that forms initially in such an environment is called PEAT. Peat is soft coal that still contains some plant materials. It has a high moisture content and the amount of carbon is still quite low.
With increasing pressure and compaction, PEAT grades into LIGNITE which has more carbon atoms in it. Lignite is more combustible although it is quite soft too. Lignite grades into SUB-BITUMINOUS coal and then BITUMIOUS coal.
The highest grade of coal is ANTHRACITE which is a hard coal. It has very little moisture content and rich carbon percentage in it. Anthracite yields more energy compared to other forms of coal. Anthracite is basically coal that forms at the greastest pressure. Beyond this pressure, a metamorphic transformation occurs and the coals changes to graphite.
Based on increasing pressure:
PEAT< LIGNITE< BITUMINOUS COAL < ANTHRACITE
Human activity has a great impact on waterways. Decreased amounts of vegetation leads to erosion of water banks. Increased fertilizer and nutrients levels in water from agriculture, sewage, and industry lead to the formation of algal blooms and subsequent decrease in other aquatic organisms.
Siberia is a vast region, mostly in the territory of Russia, and it is divided into three large regions.
<em>
Western Siberian Plain/Lowland
</em>
Located between the Ural Mountains and the Yenisei River. Occupies the western part of Siberia, and it is mostly composed of lowlands covered with dense forest, the taiga. The northern part is dominated by the tundra.
<em>Central Siberian Plateau
</em>
Located between the Yenisei River and the Lena River. Occupies the central part of Siberia, and it is mostly dominated by a plateau which gains in height on the southern part and is lowering on the northern part. The lower parts are covered with the taiga, while the higher are barren. The northern part is dominated by the tundra.
<em>East Siberian Highlands
</em>
Located between the Lena River and the Pacific Ocean. Occupies the eastern part of Siberia, and the dominated land forms are the mountains, mostly the Kolyma Mountains. Depending on the elevation, the lower parts are covered with the taiga, while the higher are barren. The northern part is dominated by the tundra.
Primary Consumers are also known as the ones who eat plants . They are usualy herbivores
The correct answer is - a. having differences.
The term heterogeneous is a term used to describe something that is different, that is not the same, or that there's multiple different things. This term can be used for various different things, including human societies, geography, biodiversity, etc.
In the human society, heterogeneous, is used as term when there's societies where multiple different ethnic groups live in a same area, or different racial groups, it may also be used in a manner of representation of the sexes in a particular filed or job, even the architecture and the infrastructure.
