Solve the following formula for the indicated variable. What does the formula describe? 
L = 2πrh for r

• A. lateral area of a cone, r = 2πLh
• B. lateral area of a square pyramid, r = 2πh/L
• C. lateral area of a cylinder, r = L/2πh
• D. lateral area of a pentagonal prism, r = Lh/2π

Answer: (C)