The Allen-Connected Graph

Right-click a vertex or edge and select "Object Properties" to color it.

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1. Is this graph planar? If so, draw the graph so that it is planar. If not, give reasons and explain why.

2. Outline an Eulerian graph. If this is not possible explain why.

3. What is the minimum amount of colors so that if each vertex were to be assigned a color, no two adjacent points would have the same color (the chromatic number)? Color them.

Allen Cheng, Created with GeoGebra