What tale of the cross-dressing Leonore was Beethoven's only opera?

More Questions:

What sport has thirteen players per team in "league" rules but fifteen in "union" play?

In NATO's phonetic alphabet, what is the letter "F" referred to as?

During what war was the novel "Simplicissimus" set?

During what war was the novel "For Whom the Bell Tolls" set?

Is Salton Sea fresh water or salt water?

Which US state capital is both the oldest and the highest in the country?

Bridgetown is the capital of which Caribbean island?

What planet was named after the goddess of beauty?

From which bridge did Barry Miller fall from in the 1977 movie "Saturday Night Fever"?

What was the name given to the first German democracy established in 1919?

What US state is represented by the figures of Oliver Morton and Lew Wallace in the Capitol's Statuary Hall?

What year did Oliver Cromwell die?

What country presented the US with a gift of cherry trees in 1912?

What is a sphygmomanometer used to measure?

Who starred in the role of Ben in the TV show "Bonanza"?