Answer:
A = 4000 years
Explanation:
Given data:
Half life = 2000 years
Total mass = 100 g
Mass remain = 25 g
Time taken to reduces to 25 g = ?
Solution:
At time zero = 100 g
At first half life = 100 g/2 = 50 g
At 2nd half life = 50 g / 2 = 25 g
Time taken:
Half life = Time elapsed / number of half lives
2000 years = Time elapsed / 2
Time elapsed = 2000 years × 2
Time elapsed = 4000 years
25 times with 2 heads, 25 times with two tails, 50 times with one head and one tail.
