I was able to identify the sources for most of the cartoon eyes without help, but I’m still completely stuck on the fifth panel. I’m not going to name the others, so as not to spoil the guessing game for everyone else.
P.S. Stay away from GoComics, their idiotic “featured comment” gimmick betrays the rest of the answers.
Comics I Don't Understand 
The fifth panel shows the “pie-eyes” typical of early Disney cartoon characters like Mickey and Minnie.
The one I don’t get is panel 2. They’re too generic. Unless it’s supposed to be Little Orphan Annie?
@ Powers – Thanks for the lead. I was not able to find “pie-eyes” anywhere in Disney’s early works,† but those eyes were definitely used for a number of other (non-Disney) animation characters of that era, such as “Bosko“:
P.S. (†) Mickey’s design was “updated” (or rather backdated) by Paul Rudish to include pie eyes, starting in 2013:
P.P.S. @ Powers (1) – I also agree with you that the second panel must be Little Orphan Annie, but it was the very last panel that I was able to identify. All the others (except #5) were much easier.
P.P.P.S. @2 – All of the “real” examples I was able to find had the “highlight” effect on the pie-eyes pointing in the same direction. Perhaps if Hamhock had not been “crossing” his eyes in the fifth panel, that might have made them easier to identify?
Spongebob?
@ john (5) – Precisely. The sixth panel was my second to last identification. Not having figured out the fifth panel, I was still trying to think of a comic strip that would fit it.
P.P.P.P.S. @4 – I decided to try rotating the eyes to see whether the alignment would make them look more like old style cartoon characters (edited to add another option):
The “left” alignment matches Mickey, and the right version is the way Bosko’s eyes appear (in the examples above @2).
I’m stuck on #4. I feel like I know it, but it’s just not coming to me. The last one was the easiest for me.
@ Susan (8) – I’ll give you a (not so) subtle hint: “Lasagne”.
According to the Walt Disney Family Museum, the Disney mostly used the pie-eyes in print comics rather than theatrical cartoons: https://www.waltdisney.org/blog/evolution-mickey-mouse#:~:text=Starting%20in%201929%2C%20the%20era,earlier%2Dmentioned%20black%20oval%20eyes.
@ Powers – Thanks again for tracking down that evolution article.† I discovered that Bosko’s eyes were handled exactly the same way as Mickey’s: he has the pie eyes only in the still drawing on the title card of this cartoon; his eyes revert to the plain dots for all of the animation. Presumably the continuity of the angled cutouts was too laborious to manage for the intermediate drawings in the cartoons.
P.S. (†) – The sample drawings of Mickey shows that the orientation of the eyes depends on the position of the character: