Comparing Volumes of Revolution

Consider four solids generated by revolving the following regions about the x-axis over the interval $[0, 1]$:

• Region 1: Bounded by the graphs of $y=x$ and $y=x^2$.
• Region 2: Bounded by the graph of $y=x^2$ and the x-axis.
• Region 3: Bounded by the graph of $y=x$ and the x-axis.
• Region 4: Bounded by the graph of $y=\sqrt{x}$ and the x-axis.

Without performing integration, arrange the solids corresponding to these regions in order of increasing volume.