How many milligrams remain of a 27 mg sample of radium-226 after 1758.9 years? The half-life of radium-226 is 1599 years.

1. 2.22684

2. 0.904959

3. 0.616087

4. 0.474106

5. 0.431845

6. 12.598

7. 0.516079

8. 23.3296

9. 1.03201

10. 19.7944

Answer in units of mg.