Answer:
D.All of the above
Explanation:
Properties of hydrogen:
1.It is lighter than air.It has density about 0.089 g/L.
2.Hydrogen rapidly change from liquid state to gas,so special protection is required to protect it.
3.It is highly flammable gas.
4.Liquid form of hydrogen exits at -432 F .This is very low temperature so special protection requires to keep it in liquid form.
Answer:

So the bouy does not float with its axis vertical
Explanation:
From the question we are told that:
Diameter 
Length 
Weight 
Specific weight of sea water 
Generally the equation for weight of cylinder is mathematically given by
Weight of cylinder = buoyancy Force

Where

Therefore

Therefore
Center of Bouyance B

Center of Gravity

Generally the equation for\BM is mathematically given by

Therefore

Therefore

Therefore

So the bouy does not float with its axis vertical
Answer:
a fluid power engine okk done please
Answer:
Explanation:
The first reported attempts to strengthen concrete flexural elements by externally bonded steel plates were attempted in France around 1964-65 and practical applications date back to 1966-67 in France and South Africa then followed by Japan and Russia.
It is High system pressure