How does nuclear fusion happen?​

Iknow the answer is a but i don't know why

About 70 percent of the earth's surface is water-covered, and about 96.5 percent of all earth's water is salt water. identify the watery feature on earth that is made of freshwater rather than salt water. a) bay b) glacier c) ocean d) sea it is not incomplete this is the true question

Hey guys so i need to know what is _nh3+> nh4oh ~chemistry~