First to start, you should start your own log/thread to ask these questions.

Yes, if they are feminized they should be females, but I think (not sure) there is still a chance you could get a male. Also, it is said that some (not sure which strains) feminized seeds have a tendency to hermie. Also, your yield depends on the amount of light your plants receive, along with tons of other factors including: Temp, humidity, ph given, nutes (also how much given), genetics of the plant (if it's known to give high yields). If you can pull out at least a whole zone off one plant than that's is pretty respectable in my opinion. Possible to get a LOT more also depending on your growing style for the plants. LST, SOG, ScrOG, Topping, FIMing..... I think you need to start by reading the sticky's in the growing sections!

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