What are the products of light reactions?

Embryos of different species look very similar, which shows that the organisms share a ancestor.

Harry lives in a city, and he has a lung condition known as asthma. on certain days, harry has to stay inside because pollutants in the air make it difficult for him to breathe. which of these pollution sources are nonpoint sources that might bother harry if he goes outside? choose the two that apply.

How many valence electrons are in atom of radon?