When 0.000028 is expressed in scientific notation, what is the exponent of 10?

• A. -4
• B. -5
• C. -7
• D. -6

Answer: (D)

Verified step by step guidance

1. Identify the original number: 0.000028.
2. Recall that scientific notation expresses a number as \(a \times 10^{n}\), where \$1 \leq a < 10\( and \)n$ is an integer exponent.
3. To convert 0.000028 to scientific notation, move the decimal point to the right until you have a number between 1 and 10. Count how many places you move the decimal point.
4. Since you move the decimal point 5 places to the right, the exponent \(n\) will be negative because the original number is less than 1.
5. Therefore, the number in scientific notation is \$2.8 \times 10^{-5}\(, and the exponent of 10 is \)-5$.