Me fast while the gas molecules that exist in the are very hot, it is still very cold because there are so few of them. a. troposphere b. stratosphere c. exosphere d. thermosphere

The correct answer is option D, Thermosphere.

Thermosphere lies between the exosphere and the mesosphere. In the thermosphere the air is very hot where the sun’s energy causes the nitrogen and oxygen gas molecules to become electrically charged. The lower layer of the thermosphere is known as ionosphere and the outer layer gradually extends into outer space with no definite outer boundary.  

the dissolution of polymer can be thermodynamically described in 2 steps.

answer is: nuclear fusion produces elements that are heavier than helium.

nuclei combine to form a heavier nucleus, releasing energy.  

for example, fusion of hydrogen atoms at the sun.  

this fusion nuclear reaction is in the inner core of the sun and hydrogen (atomic number 1) is conveted into helium (atomic number 2).  

the inner core is the central region of the sun and all solar energy is produced in the core by nuclear fusion.