Can u tell me which country is smallest in the world?

Vatican city.

Explanation:

Vatican city is an enclave located in the city of Rome, Italy.

The smallest country in the world is Vatican city also known as Holy See. It is measuring about 0.19 square miles in size and as such characterized by a very little population.

Basically, Vatican city is the central home of the catholic church and it does not have any permanent citizen. Therefore, citizenship is only granted to the people who work at the Vatican and it is revoked immediately they stop working there.

Additionally, the official language of the Vatican city is Italian and Latin.

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.