Answer:

Step-by-step explanation:
Given


Required
Determine the changes in the account
First, we need to determine the total amount spent;



<em>Hence, the changes in her account is a debit of $9 i.e. -$9</em>
I believe the correct answer is D.
Step-by-step explanation:
Distance = rate × time
If B is the rate of the boat, and C is the rate of the current, then we can write two equations:
18 = (B + C) × 3
18 = (B − C) × 9
Simplifying the equations:
6 = B + C
2 = B − C
Add the equations together to eliminate C:
8 = 2B
B = 4
Plug into either equation to find C:
C = 2
The boat's rate is 4 mph, and the current's rate is 2 mph.
Answer:
(3m2n4)^3
Step-by-step explanation:
This deals with raising to a power.
(3m2 • (n4))3
m2 raised to the 3 rd power = m( 2 * 3 ) = m6
n4 raised to the 3 rd power = n( 4 * 3 ) = n12