We can calculate how long the decay by using the half-life equation. It is expressed as:
A = Ao e^-kt
<span>where A is the amount left at t years, Ao is the initial concentration, and k is a constant. </span><span>From the half-life data, we can calculate for k. </span> 1/2(Ao) = Ao e^-k(30) <span>k = 0.023 </span> 0.04Ao = Ao e^0.023(t) <span>t = 140 sec</span>
The answer is A: When the energy transporting sediments diminishes, the sediments settle in a low-lying area; therefore, deposition always follows erosion
