Problem: the radius of a cone is 4 m , height 5 m . find the curved surface area ?
Rationale: "cone curved surface area = π rl = 22 / 7 × 4 × 5 = 440 / 7 = 62 6 / 7 slant height ( l ) = √ r ( power 2 ) + h ( power 2 ) = √ 16 + 9 = √ 25 = 5"
annotated_formula: volume_cone(4, 5)