Misc: The quetzal is the currency of ______?

Questions

Which British physician, 1749 to 1823, developed the first effective vaccine against smallpox?

For the development of a vaccine against which disease is Jonas Edward Salk best remembered?

In which city were the summer Olympic Games of 1900 held?

In 1984 Los Angeles hosted the Summer Games, which city hosted the Winter Games that year?

Which group of Australian origin had a top twenty hit in 1965 with The Carnival is Over?