11-1

> x:=cos(t):

> y:=sin(t):;

> z1:=0:

> z2:=1+x:

> z:=(1-s)*z1+s*z2:

> p:=plot3d([x,y,z],s=0..1,t=0..2*Pi,scaling=constrained):

> p;

> with(plottools):;

> vrml(p,"c:/program files/maple 6/beauty/11-1.wrl",background_color=white);

>