Respuesta :
I think the correct answers are the half-life varies depending on the isotope, half-lives range from fractions of a second to billions of years and half-life of a particular isotope is constant. Half-life is a constant value for a specific isotope that tells when does the mass of the isotope reduces to half of the original mass. Hope this helps.
Answer:
1,4,5. They are correct.
Explanation:
I got in on edg.