To express the number \(0.000000003\) in the form of \(a \times 10^n\), we can rewrite it as follows:
- Move the decimal point 9 places to the right, which will give us \(3\).
- Since we moved it to the right, we need to multiply by \(10^{-9}\).
Thus, \(0.000000003 = 3 \times 10^{-9}\).
The correct response is:
3 × 10^−9.