A small tutorial video of how to make a geodesic dome on Google Sketchup since I noticed that there wasn't one up anyway. :)
This dome is made using a decagon (10 sided polygon) as a base where it has a radius of 10 feet.The angle for the quarter is 90 and the angle for the replicated half is 180 degrees.
I'm sorry the measurements aren't completely visible in the video.
The man in the images is about 5' 10" just to give you a sense of scale.
Another alternative to replicating the quarter is to make each quarter which will give you the same result :)