Question

What is 0.0004 in standard form?

Answer 1

move the decimal to the right 4 places to get 4 x 10^-4  which reads four times ten to the negative fourth power

Answer 2

4 x 10^-4
10^-4=10 to the power of -4
Since you move the unit 4 four places to the right, it is 10^-4

I hoped I helped :)