are there back packs aloud

There are but they should be quiet

There are no signs saying that you can't bring them, but expect them to be searched.

Hmm. Don't know. My daughter-in-law and I had fairly sizeable purses. I'm betting in this post 9-11 world they would want to search your backpack but calling them would give you better info.

Yes

I usually bring a purse and my knitting bag. I have not had either searched. So it should be ok to bring a backpack.

Did not see any signs to tell its not allowed.

they don't spefically prohibit it. but respect them by not bringing any foods or drinks inside the backpacks.