Answer:
The rate of the volume increase will be 
Step-by-step explanation:
Let's take the derivative with respect to time on each side of the volume equation.

Now, we just need to put all the values on the rate equation.
We know that:
dR/dt is 0.04 cm/s
And we need to know what is dV/dt when R = 10 cm.
Therefore using the equation of the volume rate:


I hope it helps you!
Answer:
31
Step-by-step explanation:
Plug in 3 for x in the expression:
4(3²) - 5
Note that there are no parenthesis (other than the one I added, to make it easier for you. Follow the order of operations, PEMDAS. PEMDAS = Parenthesis, Exponents (& Roots), Multiplication, Division, Addition, Subtraction, and the left -> right rule.
First, solve the exponent:
4(3²) - 5 = 4(3 * 3) - 5 = 4(9) - 5
Next, solve the multiplication:
4(9) - 5 = 36 - 5
Finally, subtract:
36 - 5 = 31
31 is your answer.
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Okay so pretty much what you need to do is add the three numbers together in order to get your total. 10.2+13.75+12= 35.95 gallons. 35.95 would be the total amount of gallons of gas that was bought last week.