Explanation:
The ancient Chinese invented many aspects of money and economics used today. They minted the first coins and printed the first paper money in history, and they were pioneers of the concept of taxation. Additionally, their trade network, the Silk Road, made the country very rich by connecting buyers and sellers.
Yes it is top ranked green on earth
The development of the population policies in the 20th century were due too multiple factors, the most important of which were:
- Fertility rates were starting to lower down, especially in the ''western world'' in the second half of the 20th century.
- Increased demand for labor force.
- The World Wars, especially the second one caused huge migration movements.
- Millions of people from less developed countries were trying to migrate to more developed countries in search of a better life.
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
