Explanation:
It is given that,
The volume of a right circular cylindrical, 
We know that the volume of the cylinder is given by :
............(1)
The upper area is given by :
For maximum area, differentiate above equation wrt r such that, we get :
r = 1.83 m
Dividing equation (1) with r such that,
Hence, this is the required solution.
Iodine-131 has a half life of 8 days, so half of it is gone every 8 days.
10 grams of iodine-131 is left for 24 days.
At 8 days: 10/2=5 grams left
At 16 days: 5/2=2.5 grams left
At 24 days: 2.5/2=1.25 grams left.
**
Your mistake is that you stopped at 16 days.
Answer: 4.
Explanation:
Use formula v = d / t, where v = speed, d = distance and t = time.
v = 10 / 2.5
v = 4.
Can neither be created or destroyed.
