the radius of a cylinder is 6 m , height 21 m . the total surface area of the cylinder is ?
"total surface area of the cylinder is = 2 π r ( r + h ) = 2 × 22 / 7 × 6 ( 6 + 8 ) = 2 × 22 / 7 × 6 ( 14 ) = 44 × 12 = 528 m ( power 2 ) answer is b ."
multiply(circumface(6), 21)