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what does he like about his job？
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Part C
Directions: Answer questions 71-80 by referring to the following games.
Note: Answer each question by choosing A, B or C and mark it on ANSWER SHEET 1. Some choices may be required more than once.
Answer questions 71～80 by referring to the following games.
Note：Answer each question by choosing A, B, C or D. Some choices maybe required more than once.
A=Hydro power B=Nuclear power C=Solar power D=Wind power
Which power(power's)…
A
Hydro power
Introduction
We have used running water as an energy source for thousands of years, mainly to grind com.
The first house in the world to be lit by hydroelectricity was Cragside House, in Northumberland, England, in 1878. In 1882 on the Fox River, in the USA, hydroelectricity produced enough power to light two paper mills and a house.
Nowadays there are many hydro-electric power stations, providing around 20% of the world's electricity. The name comes from“hydro”, the Greek word for water.
How it works
A dam is built to trap water, usually in a valley where there is an existing lake.
Water is allowed to flow through tunnels in the dam, to turn turbines and thus drive generators.
Advantages
Once the dam is built, the energy is virtually free.
No waste or pollution produced.
Much more reliable than wind, solar or wave power.
Water can be stored above the dam ready to cope with peaks in demand.
Hydro-electric power stations can increase to full power very quickly, unlike other power stations.
Disadvantages
The dams are very expensive to build.
Building a large dam will flood a very large area upstream, causing problems for animals that used to live there.
Finding a suitable site can be difficult--the impact on residents and the environment may be unacceptable.
Water quality and quantity downstream can be affected, which can have an impact on plant life.
Is it renewable？
Hydro-electric power is renewable.
The Sun provides the water by evaporation from the sea, and will keep on doing so.
B
Nuclear power
Introduction
Nuclear power is generated using Uranium, which is a metal mined in various parts of the world.
The first large-scale nuclear power station opened at Calder Hall in Cambria, England, in 1956.
Some military ships and submarines have nuclear power plants for engines.
How it works
Nuclear power stations work in pretty much the same way as fossil fuel-burning stations, except that a“chain reaction”inside a nuclear reactor makes the heat instead.
The reactor uses Uranium rods as fuel, and the heat is generated by nuclear fission. Neutrons smash into the nucleus of the uranium atoms, which split roughly in half and release energy in the form. of heat.
Carbon dioxide gas is pumped through the reactor to take the heat away, and the hot gas then heats water to make steam.
Advantages
Nuclear power costs about the same as coal, so it's not expensive to make.
Does not produce smoke or carbon dioxide, so it does not contribute to the greenhouse effect.
Produces huge amounts of energy from small amounts of fuel.
Produces small amounts of waste.
Disadvantages
Although not much waste is produced, it is very, very dangerous.
It must be sealed up and buried for many years to allow the radioactivity to die away.
Nuclear power is reliable, but a lot of money has to be spent on safety.
Is it renewable？
Nuclear energy from
从生态学发展的时期看，研究动物生态学的时间比研究植物生态学的时间要早。()
【C9】
根据与环境中水的关系，可以把植物分为阳性植物、阴性植物、耐阴植物三大生态类型， ()
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