Final answer:
To express 0.0000010 in scientific notation, the decimal is moved six places to the right, resulting in 1.0 x 10^-6.
Step-by-step explanation:
To express the decimal number 0.0000010 in scientific notation, we move the decimal point to the right of the first non-zero digit. This means we have to move the decimal six places to the right. Therefore, the number in scientific notation is 1.0 x 10⁻⁶, which corresponds to option 3). Scientific notation allows us to write very small or very large numbers in a more compact form.