Answer:
![A=250g](https://img.qammunity.org/2022/formulas/chemistry/high-school/b2b0llvnkze8272tebkvyfyz4jsizc06ul.png)
Step-by-step explanation:
Hello there!
In this case, by considering the radioactive decay as a first-order kinetic model:
![A=Ao*exp(-kt)](https://img.qammunity.org/2022/formulas/chemistry/high-school/qto7c78x6mhqam8atypkyrevmt1bsfpf4k.png)
We can firstly calculate the rate constant given the half life:
![k=(ln(2))/(t_(1/2)) =(ln(2))/(520years)=1.33x10^(-3)years^(-1)](https://img.qammunity.org/2022/formulas/chemistry/high-school/43heza2ktt76jpssbw5ea3ht2m85y0u6bw.png)
Thus, we can plug in the elapsed time and the initial amount Ao to obtain:
![A=1,000g*exp[-1.33x10^(-3)years^(-1) *(3061-2021)years]\\\\A=250g](https://img.qammunity.org/2022/formulas/chemistry/high-school/a4t55m1sm2jshurhdaicpiauz7cc209k0q.png)
Best regards!