## Algebra: A Combined Approach (4th Edition)

$8.63 \times 10^{-5}$
First, count the number of zeros between the first non-zero digit and the decimal point (4). Now include the first digit to get 5 and move the decimal point to the right 5 places. 000008.63 Multiply this number by 10 to the negative power of 5. $8.63 \times 10^{-5}$