Answer:
A)
B)
C) τ=2326 years
Step-by-step explanation:
A)
Consider the differential equation:
Separate variables dD and dt:
Integrate: Remember that The integral of dD/D is ln(D).
And do , so:
B)
The function we have found is a function that let us know how many of Ra is after t years, so, evaluate the function at t=100:
Which rounded is 95.8.
C) For this equation it is known that the life half life τ is equal to (1/λ), where λ is the exponential number that is multiplying to -t in the D(t) function; so for this case, λ=0.00043, and the life half life is ,
which rounded is equal to 2326 years.