This is due to earths location in the solar system. Earth is in the habitat zone or the Goldie locks zone, in this zone it's not too hot or not too cold for water to exist. Other planets in different star systems have liquid oceans due to them being in the habitat zone.
Answer: Fusion
Explanation:
Combustion is a chemical reaction in which hydrocarbons are burnt in the presence of oxygen to give carbon dioxide and water.
Nuclear fusion is a process which involves the conversion of two small nuclei to form a heavy nuclei along with release of energy.

Nuclear fission is a process which involves the conversion of a heavier nuclei into two or more small and stable nuclei along with the release of energy.

C. Eastward. Acceleration is the change in speed so it can be a positive (speeding up) or negative (slowing down) acceleration
A prediction is a guess of something happening in the future.