What makes studying the beginnings of plate tectonics difficult? -the equipment needed has not been invented. -plate tectonics began when the earth formed. -radioactive isotopes are difficult to study. -rocks that old are hard to find.

The correct answer is - Rocks that are old are hard to find.

In order for the scientists to be able to study the beginnings of the plate tectonics they need a physical proof. The problem is that the oldest pieces of rocks have been subducted sometimes in the past, thus recycled in the mantle, so the proof is long gone. The oldest rocks on the planet, usually found deep into the mainland of the bigger land masses, are very rare, and very small, and on top of that, even though they are the oldest pieces of rocks, they are not the first ones that appeared, at least that is what is thought.

radiative zone

explanation    

radiative zone is the layer of the sun which energy is transferred away from the core by radiation. although, the core is the only part of the sun that produces an appreciable amount of heat through fusion. in fact, 99% of the energy produced by the sun takes place within 24% of the sun's radius.