Yes. Half life or better known as Radioactive decay is measured in TIME. Such as seconds, minutes, hours, days, years ect...
:) hope that helps you some, best of luck!
I'm sorry its A..I didn't read it correctly...
<em>I think the answer is C, Hence I would pick the answer to be B because it sounds to be more information into the answer then A/B. Hope this helps, let me know if I am right. </em>
Experimentation to determine the temperature of stars