Answer: Choice C) 0.000042
[tex]4.2 \times 10^{-5} = 0.000042[/tex]
There are four zeros between the decimal point and the 4.
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Explanation:
The exponent -5 means we move the decimal point five spaces to the left to go from 4.2 to 0.000042
If the exponent was positive 5, then we would move the decimal point five spaces to the right.