Applications of Integration - Volume of Revolution about the y-axis

Region \(A\) is bounded by \({{y}^{2}}=4x\), \(y\)-axis and \(y=3-x\).
Region \(B\) is bounded by \({{y}^{2}}=4x\), \(x\)-axis and \(y=3-x\) in the first quadrant.
Region \(C\) is bounded by \({{y}^{2}}=4x\), \(x\)-axis and \(y=3-x\) in the forth quadrant.
Find

1. volume of \(A\) rotated through \(4\) right angles about \(x\)-axis;

2. volume of \(B\) rotated through \(4\) right angles about \(y\)-axis;

3. volume of \(C\) rotated through \(4\) right angles about \(x\)-axis;

4. volume of total regions of \(A\), \(B\) and \(C\) rotated through \(4\) right angles about \(y\)-axis.