during radioactive decay atoms of a radioactive element break down and change into other atoms of another element-all at once

a) true
b) false

The answer is false (:

True

The statement is False. During radioactive decay, atoms of a radioactive element do not break down and change into other atoms all at once. Instead, they undergo a process where the unstable atomic nucleus of the radioactive element undergoes changes over time, slowly transforming into other elements. This process is known as radioactive decay.