import solids;
size(7.5cm);
currentprojection=orthographic((5,2,2),up=Z,zoom=.95);
real r1=4, r2=3, h1=5, h2=3;
path3 p1=(0,0,0)--(r1,0,0)--(r1,0,h1)--(r2,0,h1),
      p2=(r2,0,h1)--(r2,0,h1+h2)--(0,0,h1+h2);
revolution g1=revolution(p1,Z),
           g2=revolution(p2,Z);
draw(surface(g1),lightblue);
draw(surface(g2),lightred);
limits((0,0,0),(r1+2,r1+2,h1+h2+2));
xaxis3("$x$",Arrow3());
yaxis3("$y$",Arrow3());
zaxis3("$z$",Arrow3());