Difficulty: Easy
Correct Answer: -6
Explanation:
Introduction / Context:Negative powers of 10 translate directly to negative common logs, because log_10(10^k) = k for any real k.
Given Data / Assumptions:0.000001 = 10^{−6}.
Concept / Approach:Apply the fundamental log identity log_10(10^k) = k with k = −6.
Step-by-Step Solution:
log_10(0.000001) = log_10(10^{−6}) = −6Verification / Alternative check:Move decimal six places to the right multiplies by 10^6; the log therefore drops by 6.
Why Other Options Are Wrong:6 and ±5 correspond to incorrect exponents.
Common Pitfalls:Confusing the number of zeros; note there are six places after the decimal before the 1.
Final Answer:−6
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