GCSE Maths Practice: standard-form

\( \begin{array}{l}\text{Write } 0.00000045 \text{ in standard form.}\end{array} \)

Choose one option:

\( 45 \times 10^{-8} \) \( 4.5 \times 10^{-7} \) \( 0.45 \times 10^{-6} \)