Slope: (y2-y1)/(x2-x1)
(7-4)/(4-3) = 3/1
The answer is A. 3
1. The combined volume of all the tanks at the aquarium is written in Scientific notation. Keeping this on mind, you can write it as following:

2. Now, you must sum the combined volume of all the tanks and the volume of the new tank to calculate the total volume of all of them:
3. Now, you can write the result in Scientific notation, as following:

The answer is: 
Answer:
<em>Tiffany pays a total price of $9.81 for the basket of watermelons</em>
Step-by-step explanation:
<u>Percentages</u>
To increase a certain amount by a given percentage, we can first calculate the increasing amount and then add it to the original amount.
If the price of the basket of watermelons was $9 before tax, and the sales tax is 9%, we first calculate the tax amount to pay:
$9 * 9 / 100 = $0.81
Now we add it to $9 to get the total price paid by Tiffany:
Total price = $9 + $0.81 = $9.81
Tiffany pays a total price of $9.81 for the basket of watermelons
A^2 - b^2 = (a-b)(a+b)
To test it, expand the right hand side.