The rate at which a radioactive<span> isotope decays is measured in </span>half-life. The termhalf-life<span> is defined as the time it takes for one-</span>half<span> of the atoms of a </span>radioactive material<span> to disintegrate. </span>Half-lives<span> for </span>various radioisotopes<span> can range from a few microseconds to billions of years. </span>. back at it again with that answer . zane
