Help me with the definitions on these i will mark brainlist

Classify the structures as homologous or analogous, depending on their structure and function.

Legumes, a type of plant, require rhizobia, a type of soil bacteria, to survive since these organisms fix nitrogen during photosynthesis. rhizobia use the legumes for food. what would most likely happen to the legume population if rhizobia suddenly became extinct?

What function does a limb serve in each animal how are the limb bones of the four animal similar based on the similarities what can be inferred about the evolution of the poor animals