Answer:
- 4
Step-by-step explanation:
using the law of logarithms
[tex]log_{b}[/tex] x = n ⇔ x = [tex]b^{n}[/tex], hence
0.0001 = [tex]10^{-4}[/tex] = [tex]10^{n}[/tex] ⇒ n = - 4
