There aren't answers for U or X but if you have suitable data, please let me know. Accurately measuring the speeds of animals is extremely difficult when one takes into account distances, terrain, size of the animal etc etc etc. I've taken my answers from the source link and just in case you still don't agree with the answers, there's plenty of bonuses to find. Have fun!
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Can you name the A-Z of animals with the clue being their top speed? Note - the answer isn't necessarily the fastest animal for that particular letter.
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