No, I would not believe my fellow student who saw a 3-cm-long ladybug. Yes, I would believe my other fellow who caught a 10-kg salmon.
Work Step by Step
Ladybugs are of the order of millimeters in size; while 3 cm is about ten times that. It is unlikely that my fellow student saw a 3-cm-long ladybug. Salmons on the other hand can weigh 10-kgs. So, she is believable.