He started out with 19.1 gallons because if you add 5.8 and 12.4 you get 19.1
You have to do length of the base x width of the base x height of pyramid
It’s D)18 I hope this helps
Answer:

Step-by-step explanation:
We are given that a function

We have to find the average value of function on the given interval [0,7]
Average value of function on interval [a,b] is given by

Using the formula

![f_{avg}=\frac{1}{7}[e^{\frac{x}{7}}\times 7)]^{7}_{0}](https://tex.z-dn.net/?f=f_%7Bavg%7D%3D%5Cfrac%7B1%7D%7B7%7D%5Be%5E%7B%5Cfrac%7Bx%7D%7B7%7D%7D%5Ctimes%207%29%5D%5E%7B7%7D_%7B0%7D)
By using the formula


Because 

Hence, the average value of function on interval [0,7]

Common Ratio<span>. For a </span>geometric sequence<span> or </span>geometric series<span>, the </span>common ratio<span> is the ratio of a term to the previous term. This ratio is usually indicated by the variable r.</span>