Question

what is the exponent when the following number is written in scientific notation? 0.0000000085

Explanation:

Step1: Rewrite number in scientific notation

Scientific notation is of the form $a \times 10^n$, where $1 \leq a < 10$. For $0.000000085$, move the decimal 8 places right to get $a=8.5$.

Step2: Determine the exponent

Since we moved the decimal to the right (for a number less than 1), the exponent $n$ is negative, equal to the number of places moved.

Answer:

$-8$