What did the containment strategy provide a rationale for?

The Containment Strategy was the principal strategy adopted by the US in foreign policy matters during the Cold War era.

It aimed to stop the expansion of the national enemy: communism, and in turn, of the URSS and the countries under its influence, that were denominated the Eastern Bloc. It consisted on responding to any attempt of expansion performed by the URSS, seeking to spread communism in Eastern Europe, Korea, China Africa, Vietnam, and Latin America.

radioactive dating, also known as  radioisotope dating  is a process that in  estimating the approximate  age  of  rocks. these data can be analyzed from  the studies dealing with the  decay of the radioactive elements that are present in these rocks. in nature, there are a few types of materials or atoms which are quite unstable and they spontaneously decay or breakdown to form other kinds of atoms.