1. D - sound travels the fastest through solids
2. 50 mm/s - v=fa
3. B - only process that involves changing waves
Answer: 71.72 days
Explanation:
This problem can be solved using the <u>Radioactive Half Life Formula: </u>
(1)
Where:
is the final amount of Iodine-131
is the initial amount of Iodine-131
is the time elapsed
is the half life of Iodine-131
Knowing this, let's substitute the values and find
from (1):
(2)
(3)
Applying natural logarithm in both sides:
(4)
(5)
Finding
:
It’s 1.255 i believe ! good luck ahah