Misc: What is a monkey puzzle?

Questions

Where, in New Mexico, was the first atomic bomb detonated in July 1945?

By what name is the skin complaint of 'comedo' better known?

Of what is petrology the study?

Which actor and muscle man, a former 'Mr. Universe', gained fame and fortune in Italy, playing mythical heroes such as Hercules?

In what field is Romuald Rat a well-known name?