Yes, they show concentrations. The bottle label says:
"Contains approximately 500mg CBD* and other cannabinoids. (*Cannabidiol)"
Also the label states it is "hemp whole plant extract" not seed or stalk exclusive.
I take from half a dropper up to 2 droppers a day and I've only bought the 2 oz bottle. It lasts approx 4 weeks. I just yesterday received my second bottle.
No, I haven't used food-grade hemp oil. Seems like a waste of time because the concentrations are so low but there you have it.