Answer:
The effort put by scientist and sailors about earth is that they keep on going round the earth and putting their lives in danger and some even give their lives.
Explanation:
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The best answer is (1)
Fossil fuels are commercially available as an energy source.
They are very easy to find. More and more extractions of fossil fuels is going on everyday. With advancement in science and technology, the refineries and extraction procedures have improved a lot. This makes their availability even better.
Fossil fuels are also easily combustible. Most combustion engines need to be powered with little amount of fuel to produce large amount of energy. Very large amounts of electricity can be generated from fossil fuels.
Answer: What is expected to happen is that the secondary immune system acts immediately against the virus.
Explanation:
When a virus first enters our body, in order to defend itself, the body must first recognize what the antigen is in order to fight it through <u>antibodies</u>. Once it does it will keep a memory of it that it can use if this virus enters the body again. <u>This will be done through the secondary immune system</u>.
As the body already recognizes the antigen, it knows how to fight it immediately, generating a thousand times the amount of antibodies generated the first time.
Thanks to its memory cells, the virus will remain much less time in the body.
An organism ultimately must obtain all of the necessary energy for life from its environment
