a hypothesis is an idea or explanation that you then test through study and experimentation
Answer: 
Explanation: A double displacement reaction is one in which exchange of ions take place.
The compounds which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
Thus the exchange of ions take place and all the compounds are soluble so the chemical formulas are followed by the symbol (aq).
Answer:
Nuclear fission
Explanation:
All nuclear reactors in operation are based on the principle of nuclear fission of Uranium nuclide to produce energy. These is produced is being controlled and is used in heating water to steam. The steam is then harnessed to drive or power steam turbines which is used for the generation of electricity.