The modern era of flight lifted off in 1783 when two brothers demonstrated their invention, the hot air balloon, before a crowd of dignitaries in Annonay, France.
There are two oxygen atoms. The OH is in parentheses with the 2 after it to indicate that there are two OH molecules, each containing on atom of oxygen.
Green roof do have several advantages over ordinary roofs as follows.
<h3><u>Explanation:</u></h3>
Green roof are defined as the roof over which a thin layer of soil is placed to grow a thin layer of grass or other plants. This have several advantages as follows:
A. Green roof help in reducing water logging in roofs, thereby reducing the dampening of the concrete, and increasing the longevity of the roof.
B. It is actually energy saving, by reducing the summer temperatures by evaporation and transpiration. It also maintains a warm room temperature in winter by reducing the heat loss.
C. It's also actually low in budget. Its initial cost is more than ordinary roof, but the maintenance cost is very low, if not nill.
D. Its a place for recreational activities. Greenery in urban areas are very rare sight, which can be met through this project.
E. Green roofs provide a chance for urban agriculture.
The placenta provides oxygen to the baby and excretes carbon dioxide into your bloodstream.
meaning that the baby does not simply absorb oxygen from a women's bloodstream. blood and gas transports occur through the placenta, also the placenta delivers oxygen-rich blood through the umbilical vein not artery
hope this helps
The dark reaction of photosynthesis is called the Calvin cycle or Calvin - Benson cycle.
It is a series of chemical reactions that occur in chloroplasts during photosynthesis.
It is also known as the light - independent phase because it happens after light energy ahs been absorbed from the sun.
It is named after scientist called Melvin Calvin who was the winner of a Nobel prize in chemistry for finding how this cycle works way back in 1961, at the university of California.