Find the volume of the solid generated by revolving around the x-axis

the region bounded by the x-axis, and one arch of the cycloid

x = t−sint, y = 1−cost.

where 0 ≤ t ≤ 2pi.

[ Hint : Use the disk method and dV = piy2dx = piy2(dx/dt) dt ]

I'm confused on this problem. I think it's because I don't actually know what they're asking... Is y the upper and x (t-sint) the width?