It looks like a spiral in 4-dimensional space!
A quadrangle is a closed 2-dimensional shape bounded by four straight lines.
It does not look like a spiral because we are inside the disk that forms the spiral arms. To see the spiral, you have to be outside the galaxy, viewing the disk from above or below.
A tesseract is a four-dimensional shape, so it is impossible for humans to visualize it in our three-dimensional world. We can only represent it through mathematical models or computer graphics that attempt to depict how it would appear if we could see in four dimensions.
It means the galaxy has the shape of a spiral. To see what this looks like, search Google Images (image.google.com) for examples.
A spiral length of something, like a spring.
The answer is ammonite
A spiral, I think.
The milky way has no definite surface, however from a distance it would look like a barred 2 armed spiral with some of the spiral arms bifurcating.
Any photo that isn't a 3-dimensional photo is a 2-dimensional photo.
Flat
one dimensional
A tetrahedron, but you can also think of it as a pyramid. -edit: actually it would be a pentahedron, which may look like a four sided pyramid in which you can see the bottom, or it may look like a triangular prism. Tetra- four, Penta- five.