How to map the field of a variable quantity

To map the field of a variable quantity, you will want to use a system of temporary reference points within the field. This way, you'll be able to move within the study area without losing your geographical references. You'll be able to map things like trees, allowing you to make repeated measurements and verify your data.

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.