With bills and throats visible, it's much easier to I.D. these three birds as (left to right) 1) a Brandt's Cormorant; 2) Pelagic Cormorant, and; 3), Double-crested Cormorant. In the quiz photo, the bird on the left shows a conspicuously shorter tail than the similarly-sized bird on the far right. Double-crested Cormorants are long-tailed, so bird #1 becomes a Brandt's by process of elimination; it's too large to be a pelagic, and too short-tailed to be a Double-crested.

The middle bird is clearly smaller than the other two, so Pelagic is probable, but a runt bird is always a possibility. However, the thin bill provides us with the necessary additional information to confirm this I.D.

The right-most bird not only shows a long tail, but also has some scalloping on the back often seen on Double-crested Cormorants.

In the answer photo, the telltale marks are the buffy throat on bird 1; thin bill and neck on bird #2, and orange throat/facial patch on bird 3.