Answer:
log(0.0003) = -3.5229
Explanation:
The rules of logarithms tell you ...
log(ab) = log(a) +log(b)
Application
log(0.0003) = log(3×10^-4) = log(3) +log(10^-4)
= log(3) -4 = 0.4771 -4
log(0.0003) = -3.5229
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Additional comment
If you do much work with logarithms, you find that negative logarithms are generally expressed using a positive mantissa with a negative add-on. Often, that negative add-on is -9, so this would be ...
5.4771-9
This helps when taking antilogs, as you look up 0.4771 in the table to see that the multiplier is 3.
If you were to look up 0.5229, you would find 3.333, meaning the multiplier is 1/3.333 and the antilog of -3.5229 is (10^-3)/3.333. This may not be a convenient value to work with.