She underestimated by 60 cents. To get this answer all you need to do is multiply 1 dollar times 12 which is $12 and then multiply $.30 by 12 and that gives you $3.60. Then you add the $12 to the $3.60 and that gives you $15.60 which is 60 cents over the estimation.
Answer:
stack AD with bar on top space text is parallel to end text BC with bar on top.
A. 8^9/2= around 11585.2375; (sqrt8)^9= around 11585.2375. So choice A shows a pair of equivalent expressions.
B. (3sqrt125)^9=1,953,125; 125^9/3=1,953,125. So choice B also shows a pair of equivalent expressions.
C. 12^2/7= around 2.03394; (sqrt12)^7= around 5,985.96759. So choice C does not show a pair of equivalent expressions.
D. 4^1/5=around 1.31951; (sqrt4)^5=32. So choice D also doesn't show a pair of equivalent expressions.
Your answers are A and B.
I hope this helps ;)
The first one is 24 the second is 96
Prime factor is a factor that is a prime number.
Prime factors of :
8 : 2 × 2 × 2. Also can be written as

12 : 2 × 2 × 3. Also can be written as

20 : 2 × 2 × 5. Also can be written as

30 : 2 × 3 × 5
56 : 2 × 2 × 2 ×7. Also can be written as

70 : 2 × 5 × 7
You can find all of them by using Factor Tree [ as shown in the picture] or Dividing by prime numbers.