This is false. There are many factors, like climate, fires, pollution, etc.
1/3 probability would be the answer
The whale's flipper and tail flukes and fish fins are analogous structure as they have different structural formation but they perform the same function.
Flipper and tails are locomotory organs in the whale and helps the whale in propelling similarly fins in the fish assist the fish in swimming. Both the strcutures have evolved differently and are made of different materials.
For the answer to the question above, I believe that <span>the mutation is likely in any type of regulatory sequence.The mutation is probably acting to reduce or prevent transcription initiation.</span>
I hope my answer helped you in some ways.