Nice, How can you tell its a Cooper's Hawk?
First - overall brownish color. This is common to a few hawks but includes juvenile cooper's. (Most of the other options have other marks that we
don't see here - too many options to list, but for example, a harrier would have a very obvious white rump from this angle.) More important, length of tail. This narrows it down to an
accipeter. Next, the particular pattern of tail stripes. This confirms it's either a Cooper's or a Sharp-shin. Telling those two apart can come down to very hard-to-judge impressions of things like the size of the head vs the rest of the body. An easier way is that Coopers' has some tail feathers shorter than others, and you can see that here if you look closely.