Answer:
The mass of Uranium present in a 1.2mg sample is [tex]4.8 \cdot 10^{-6}\,mg[/tex]
Explanation:
The ration between Uranium mass and total sample mass is: [tex]\frac{4g}{1000kg} =\frac{4g}{1000000g}=\frac{1}{250000}[/tex]
For a sample of mass 1.2 mg, the amount of uranium is:
[tex]1.2\, mg \cdot \frac{1}{250000}=4.8 \cdot 10^{-6}\,mg[/tex]
