Answer:
1 - The cartoonist is possibly trying to convey 1 of 3 things: that people will tend to assume a situation isn't bad just because they can't see the full extent of the conflict, people would rather fill in the blanks of what they don't know with a pre existing beliefs that may or may not be true and just leave it at that, or just because whatever makes a situation bad is present in one circumstance doesn't mean it can't be harmful in another circumference.
2 - The crocodile is smiling almost mischievously, indicating that it's aware of its surroundings and the situation that its in and knows that it can act on the fact that these humans are scared of him, and frankly he looks proud as if thinking to himself "Yes fear me humans, you will respect my capabilities". Not to mention its face is shown to be as developed as the two people and is featuring human like emotions such as pride. Additionally the crocodile is on a bicycle which, as far as I know is strictly a human thing to ride.
3 - The one who's initially afraid of the croc seems to acknowledge the fact that the crocodile is an animal that shouldn't be messed with, and fears what they can do. The second who arrives after, believing that it's safe to assume that crocs are slow on land, reassures the other even though he may not know completely himself. I'd say that the first character is rational and is right to be cautious around a crocodile and the second one is more quick to believe that crocodiles can't be that bad and they should only be feared in the water.
4 - Obviously the character makes the false assumption that just because the crocodile is fast in the water, there's no evidence to conclude that the crocodile CAN'T be fast on land as well. Therefore his assumption is irrational.
5 - The cartoonist exaggerates the frame by adding a bicycle in which the crocodile sits atop. This is an exaggeration because crocodiles don't need bikes to move around, on land or in the water, and would be unnecessary for chasing them.
6 - The characters' interaction uses words to downplay the severity of the situation and make it seem as everything is alright, and the first few frames supports this. Yet we see that the crocodile is on a bike, which is quite an odd and almost hilarious site to witness, and could possibly use it to chase them but only we the audience knows this.