Answer:b. gravitational, kinetic, thermal
Explanation:
The above explains the mechanism of the core forming process on earth/planet.
It is believed that this process might has contributed significantly to a planet's early stages heating. The time when these core-forming event happened is thought to have been mainly completed very early when Earth was young . The type of this event rather than it being seen as a single catastrophic event, it is likely to have been as a result of contractions on the earth severally.
The addition of partially differentiated material from another giant impact the rate of this spasm , and it increases each time the planet's mass is to increased.
This is a little on the history of planetary evolution.
If the prefix mega is added to the unit of the quantity being described, the magnitude of quantity increases by 10^{6} times i.e. 1 million times.
For Example- 1 MW = 1000000 watts
: A chemical process of decomposition involving the splitting of a bond by the addition of water.