The answer of this question is D
Answer:
E
Explanation:
100 minutes is 5 half lives ( 100 min/20 min/half life)
= (1/2 )^5
1 x 10^20 * (1/2)^5 = 3.125 x10^18 molecules
<span>The answer is curie.
</span>
Mass is an amount of substance present in a body. mass is measure with the help of triple beam balance. the unit of mass are kilogram, gram etc.
