Sketch in Cylindrical Coordinates for z=6

[ZedCar]

Homework Statement

In cylindrical coordinates, sketch the surface defined by z=6

The hand drawn sketch shown in the answer I have appears to be a rectangular or square plane at z=6

Should the plane be square/rectangular or should it be circular?

To illustrate, the blue plane in the diagram linked-to below is the z-coordinate;
http://en.wikipedia.org/wiki/File:Cylindrical_coordinate_surfaces.gif

Thank you.

Homework Equations

The Attempt at a Solution

 

[tiny-tim]

Should the plane be square/rectangular or should it be circular?

Infinite!

 

[ZedCar]

Infinite!

Ah, yes of course.

Thanks tiny-tim.