A right circular cylinder has radius $3$ and height $6.5$. What is its total surface area (including both circular bases and the lateral surface)?

The total surface area of a right circular cylinder is the sum of three pieces — two congruent circular bases (each $\pi r^{2}$) and one lateral surface ($2 \pi r h$): $A = 2(\pi r^{2}) + 2 \pi r h$. With $r = 3$, $h = 6.5$: - Two bases: $2 \pi (3^{2}) = 18 \pi$. - Lateral: $2 \pi (3)(6.5) = 39 \pi$. - Total: $18 \pi + 39 \pi = 57 \pi$. - Trap A ($18 \pi$) counts only the two bases and forgets the side. - Trap B ($39 \pi$) counts only the lateral surface and forgets the two ends. - Trap D ($58.5 \pi$) returns the **volume** of the same cylinder. Key check: the lateral surface area $2 \pi r h$ is just the circumference of the base ($2 \pi r$) times the height — i.e. the area of the rectangle you'd get by 'unrolling' the side of the cylinder flat.