CLOSED: Tell me what this bird is, please!! Oh please hurry! :-)

I'm so excited, this hawk(?) let me take over 300 pictures. I haven't looked closely at them all yet but in one I noticed yellow corners to its mouth as if it was a very young bird. Maybe these birds have yellow corners even when they are grown? Maybe I was interpreting what I saw incorrectly. This bird was really big compared to a Sharp-shinned. It was so unconcerned by traffic, by a lady walking her dog and me clicking away with my big black camera.
Have pictures from the back, side and even under one wing too if needed for ID.

Huge thanks in advance!

Red-tailed Hawk, immature (which is why its tail isnt reddish!)

Resin

I took out the line where I said I thought it "looked like a Red-tailed Hawk - but that the tail was wrong"
LOL, honest!
Thanks so much Resin!!!

....and it's much larger than a Sharp-shinned. Weighs 7+ times as much and has more than twice the wingspan.

Thanks OldNed! Here is a picture at take-off, not very good but it does show the dark mark on the leading edge of the wing.

Lucky Dog!!