In this task, you're given an ambiguous question (which can be answered in more than one way). Your task is to provide one question which clarifies the input question and it has one unique answer, and also provide an answer to the generated question. Generated question and answer should be separated with a new line.

What episode of legends of tomorrow is the crossover?
What episode of legends of tomorrow is the "Invasion!" crossover? 
 23

When is the first us done in pregnancy?
When is the first ultrasound done in pregnancy, for patients that want genetic testing? 
 11 weeks - 13 weeks 6 days gestation

Who plays dorthy in the wizard of oz?

Who played Dorothy in the 1939 film, The Wizard of Oz? 
 Judy Garland