Answer: There are several information's of immense importance already given in the question. Let us write them down first.
Diameter of the cylinder = 6 inches
Then
Radius of the cylinder = 3 inches.
Height of the cylinder = 3 * radius
= 3 * 3
= 9 inches
Volume of the cylinder = (pi) * (Radius)^2 * Height
= 3.14 * (3)^2 * 9
= 3.14 * 9 * 9
= 254.34 cubic inches
Hello there,
I hope you and your family are staying safe and healthy during this winter season.

We need to use the Quadratic Formula*
, 
Thus, given the problem:

So now we just need to plug them in the Quadratic Formula*
, 
As you can see, it is a mess right now. Therefore, we need to simplify it
, 
Now that's get us to the final solution:
, 
It is my pleasure to help students like you! If you have additional questions, please let me know.
Take care!
~Garebear
15818 ?? This is making me get a headache
To solve this, I would square root all of the possible answers and see which ones the arrow falls between. After that I would choose the answer closest to it.
Hope this helps!