A cylinder has radius \(r\) and height \(h\). Identify the student setup that gives its total surface area.
Student 1: \(2\pi~\text{rh}\)
Student 2: \(\pi~r^{2}h\)
Student 3: \(2\pi~r^{2}~+~2\pi~\text{rh}\)
Student 4: \(\pi~r^{2}~+~2\pi~\text{rh}\)
What this problem is really about
Judge each setup against the complete exterior of a closed cylinder. It must contain two circle-area terms for the bases and a separate circumference-times-height term for the curved side. A missing base gives only part of the surface, while multiplying base area by height changes the quantity to volume.