Answer: B. 10.70
Explanation:
So we are given how much she spent and how much it costed.
So if the mouse costed $9.30 but she paid with 20 we would just subtract
9.30 - 20 = 10.7 or 10.70
(You could also check this by adding- 10.70 + 9.30 = 20 )
So she got 10.70 change back