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They both look to be EE pullets to me.
The white one has green legs, and the black/white pattern appears to be a pullet. Silver in a pullet is a different color, while the rooster has a different pattern for the black/white in the silver color.
You can see photos of the breed standards here: http://www.ameraucana.org/gallery.html
Also, you may want to post on the Ameraucana thread to get the opinion of the experts there.