For this case the lateral area of the cylinder is given by: [tex]A = 2 * \pi * R * h
[/tex] Where, R: radius of the base of the cylinder h: cylinder height The length of the rectangle is: [tex]L = \frac{A}{h}
[/tex] Substituting values: [tex]L = \frac{2 * \pi * R * h}{h}
[/tex] Simplifying we have: [tex]L = 2 * \pi * R
[/tex] Answer: B) 2 * pi * r