If the half-life is 5 minutes, then 30 minutes is equivalent to 6 half-lives. So, after six successive half-lives, the 400 mg of the radioisotope would have a mass of 400(0.5)⁶ = 6.25 mg.
Thus, A would be the correct answer choice here.
Answer:
The answer is B:cognitive skills
I believe the answer would be the anterior.
5=true
6=c
7=D
I think these are correct but 7 might be A so yeah
