Would alligator best saltwater crocodile in hypothetical Lake Urmia battle?
Lake Urmia is a salt lake in Iran. Saltwater crocodiles have special glands that allow them to survive in salt water. Alligators lack glands to stay in salt water for extended periods of time.
The answer is no.

Have jokes killed more people than rats in history?
Greek philosopher Chrysippus was said to have died from laughter after seeing a donkey eating figs. There are only a handful of deaths attributed to jokes throughout history including King Martin of Aragon. There are an average of 30 deaths by rat attacks every century. The plague which is sometimes associated with diseased rats killed millions of people.
The answer is no.

Has categories of Nobel prizes remained same since Alfred Nobel established them?
Alfred Nobel established the Nobel prize in his will in 1895. Alfred Nobel established 5 Nobel prize categories: Chemistry, Literature, Peace, Physics, and Physiology or Medicine. The Nobel prize evolved to include a sixth category of Economic Sciences in 1968.
The answer is no.

Did George W. Bush grow up speaking Cantonese?

George Bush grew up primarily in Texas. English is the primary language spoken in Texas. Cantonese is the primary language spoken in certain parts of China.
The answer is no.