solids of revolution

Volume by integration and finding the centroid

please help me with this!!!
Im really having hard time getting this.
Region 1 is bounded by the x axis, the line x=1 and the curve y=x^2. Region 2 is bounded by the two curves y=x^2 and x=y^2. Region 3 is bounded by the y axis, the line y=1 and the curve x=y^2. Find the volume and centroid of the solid generated when the indicated region is revolved about the given line:
A. Region 1 is revolved about y axis
Region 1 is revolved about x axis
B. Region 2 is revolved about y axis
Region 2 is revolved about x axis

Volume by integration

Find the volume and centroid of the solid generated using disc and shel methods,as the region bounded by the curve y^2=8x, the x axis and the latus rectun of the curve is revolved about:
A. The x axis
B. The y axis
C. The latus rectum

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