18. The region under the curve y = 7sin x, 0 Ex S It is rotated about the x-axis. Find the volume of the resulting solid. 21 a. IT 2 147 b. TT 2 8 7 C. TT d. 21 e. 2119. Set up, but do not evaluate, an integral for the area of the surface obtained by rotating the curve y = Inx' about the x-axis on the interval I S x $ 3. a. b. J 2 min(x) 1+ dx C. 2 7( 3x) 1+ - dx d. 2m(3x) 1+ dx 3 e. 2 7(3In(x)) 1+ dx x