What are the half lives for uranium-235 and uranium-238?
a.
The half-life of uranium-235 is 713 seconds, the half-life of uranium-238 is 4.5 minutes
c.
The half-life of uranium-235 is 713,000,000 years, the half-life of uranium-238 is 4,500,000,000 years
b.
The half-life of uranium-235 is 713 days, the half-life of uranium-238 is 450 days
d.
None of the above