Answer:
3900 dg
Explanation:
We know that 1 dg equals 100 mg
Now if we have [tex]3.9. 10^5 mg[/tex] to how many dg is equivalent
[tex]100 mg \longrightarrow 1dg\\3.9.10^5mg \longrightarrow x\\x=\frac{(3.9.10^5)(1)}{100}\\ x= 3900[/tex]
So [tex]3.9. 10^5 mg[/tex] equals 3900 dg