Henri becquerel and the curies worked with uranium, radium, and polonium, all of which give off sunlight radiation elements light

Henri Becquerel and the Curies worked with uranium, radium, and polonium, all of which give off radiation.

Explanation:

Henri Becquerel and Marie Skłodowska-Curie discovered the process of radioactivity. They were awarded Nobel prize for their work. Radioactivity is the process in which an unstable element emits energy in the form of radiation. This process also produce a lot of heat. Radiations are very harmful for human health however they have wide applications in modern technology.  

the truman doctrine was an american foreign policy whose stated purpose was to counter soviet geopolitical expansion during the cold war. it was announced to congress by president harry s. truman on march 12, 1947, and further developed on july 12, 1948, when he pledged to contain threats to greece and turkey.