A 10 gram sample of pure potassium sample was 100% rubidium-87 approximately how much of the sample will still be potassium 40

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

The correct answer is "b"