Explanations appreciated

• How would I find the volume of the following: y=8x³,y= 0,x= 1;aboutx= 2
• find the volume of the following: y= sin^?1(x),y=?/2,x= 0; rotated abouty=4
• Use the method of cylindrical shells to obtain the volume of the followin
  

Let S be the solid obtained by rotating the region shown in the gure below about the y-axis