How the activity of half life decreases wirh time?

The activity of a radioactive substance decreases over time due to the process of radioactive decay, where unstable nuclei transform into more stable forms, emitting radiation in the process. Half-life is the time required for half of the radioactive atoms in a sample to decay. As successive half-lives pass, the number of remaining radioactive atoms and, consequently, the activity of the substance continue to halve, leading to an exponential decline in activity. This means that after several half-lives, the activity becomes significantly lower, approaching but never quite reaching zero.