To express the number \(0.000000018\) in scientific notation, follow these steps:
1. Identify the significant digits: The number is \(0.000000018\), and the significant digits are \(1.8\).
2. Determine the position of the decimal point:
- Initially, the decimal point is after the last zero in the sequence of zeros before 18. This is equivalent to the decimal point being at \(0.000000018\).
- To express \(0.000000018\) as \(1.8\), you need to move the decimal point to the right of 1.8.
3. Count the number of places the decimal point has been moved:
- The decimal point has been moved 8 places to the right (from \(0.000000018\) to become \(1.8\)).
4. Express in \(a \times 10^b\) format:
- Since the decimal point moved 8 places to the right, this can be expressed as \(1.8 \times 10^{-8}\).
Therefore, the correct scientific notation for \(0.000000018\) is \(1.8 \times 10^{-8}\).
So, your answer is:
[tex]\[ 1.8 \times 10^{-8} \][/tex]
