Answer:
8.4 / 10 = 0.84
Why?
When you multiply by powers, you move the decimal point to the left.
When you divide powers you move the decimal point to the right.
For example, when you are dividing 8.4 by 10 to the power of 1, or just ten 10,
you need to move the decimal point one place to the right.
Hope this helps!