Answer:
It's either a or b
Explanation:
I'm not sure which of those it would be but I hope it helps some!
A is the answer. Explanation is in the photo
1. 1.00(1/2)^151/30.2= 31.3 g
2. 24g-->1.4 g = 4 half-lives, so 4*5730= 22920 years
3. 64g-->2.0g = 5 half-lives, so 12.5/5= 2.5 hours
they both are solid at room temperture
