What is the volume formula for a cylinder using diameter?

• A. V=π•R²•H
• B. V=0.7854•D²•H
• C. V=2π•R•H
• D. V=H²

Answer: (B)

The volume of a cylinder in terms of diameter comes from the standard formula V = πR^2H, with R = D/2. Substituting gives V = π(D/2)^2H = π(D^2/4)H = (π/4)D^2H. Since π/4 ≈ 0.7854, the volume is V ≈ 0.7854 D^2 H. This matches the option that uses 0.7854 times D squared times H. The other forms aren’t correct for volume with diameter: one uses radius directly, another resembles a surface-area term, and one is just H^2.