A can of soda has 35 mg of sodium in it. How many grams of sodium is this?

$1 \cdot m g$ $=$ $\text{1 milligram}$ $=$ $1 \times {10}^{-} 3 g$
And thus $35 \cdot m g$ $=$ $35 \times {10}^{-} 3 g$ $=$ $0.035 \cdot g$.
How many $g$ in $1000 \cdot m g$?