Algebra
posted by Darwin12 .
In 10 years, 25% of a radioactive substance decays. What is its halflife?
A. 25 years
B. 24 years
C. 20 years
D. 29 years

c
posted by Darwin12 .
In 10 years, 25% of a radioactive substance decays. What is its halflife?
A. 25 years
B. 24 years
C. 20 years
D. 29 years
c