What are possible origins of Earth's surface and internal energy?

The flow of heat from Earth's interior to the surface is estimated at 47±2 terawatts (TW) and comes from two main sources in roughly equal amounts: the radiogenic heat produced by the radioactive decay of isotopes in the mantle and crust, and the primordial heat left over from the formation of Earth.

the correct answer is(the type of energy described here is potential energy.)

explanation: now if the person holding the bow and arrow has now let go. the arrow shoots forward toward its target. the   type of energy then becomes

a "theory" a suggestion that is not 100 % accurate, or a figure. some people say its a theory because they of all the passed theory's about one subject. it depends sometimes theory might be accurate and sometimes they are.