Answer:
n = 6
Explanation:
To find the exponent of 10, you can write the equivalent multiplier in standard form, then identify the place value of the 1 in the multiplier.
0.000689 = 689 × 0.000001
The 1 is in the 6th place to the right of the decimal point. The place value of digits in that place is 10^-6
0.000689 =689 × 10^n = 689 ×10^-6
n = -6
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In the attached, your number would fill in the blanks to the right of the decimal point. The least-significant digit (9) would have a value of 9×10^-6.