evaporation systems allow for an endless source of water. you can grab cups of water straight from the sea or even a lake. the use of evaporation allows for you to drink water thats even healthier than getting it from a cloud and it will leave all of the bad parts that used to be in the water in the first container you pour into. this system is most useful in hot climates such as places near the equator.
Answer: 
Explanation:
Firstly we need to know that
, then we cam make the conversion:
This is the height of Mount Everest in feet
However, we can express it using scientific notation by counting to the left the decimal spaces:

The answer is 4.
Gases have low densities, because of the increased space between hight-energy particles.
Answer
I think it’s 5
Explanation
Answer: C2H4
Explanation:
The percentage composition of ethanol ( C2H5OH ) consist of 52.2% Carbon, Hydrogen of 13.0 and 34.8% of Oxygen.
The percentage composition of ethane gas (C2H6) consist of 80.0% carbon and 20.0% hydrogen.
The composition of Ethylene Glycols i.e C2H4(OH)2 is Carbon of 39.7%, 9.7% hydrogen and 51.6% oxygen.
The percent composition of c2h4 is 86% carbon, and 14% hydrogen.
From the information given, the substance with the highest percentage of carbon is C2H4