The answer is 2268pi ft^3
UGH I think I did this before but I totally forgot how to do it. Give me a minute to do some research and remember because I'm about 79% sure I know how to do this!
Answer:
D
Step-by-step explanation:
A. false; the diameter of a circle is double the radius
B. false; the diameter of a circle is double the radius
C. false; the diameter of a circle is double the radius
D. true! The diameter is double the radius
Answer:
Second box for Justifications: Subtraction Property of equality
Third box for steps: 
Fourth box for steps: 
Fourth box for Justifications: Multiplication Property of equality
Fifth box for steps: 
6b^2 + 9b + 11 is that in simplified form. I hope that it is what you were looking for :)