Table: apollo_11_moon_landing
Columns: mission_name
lunar_lander
lunar_landing_date
lunar_blastoff_date
lunar_landing_site
duration_on_lunar_surface
crew
number_of_s_eva
total_eva_time_hh_mm

Question: Where was the landing site when the duration on the lunar surface was 21:31?
SQL: SELECT "lunar_landing_site" FROM apollo_11_moon_landing WHERE "duration_on_lunar_surface" = '21:31'

Question: Who were the crew for the Falcon?
SQL: SELECT "crew" FROM apollo_11_moon_landing WHERE "lunar_lander" = 'falcon'

Question: What is the average number of EVA for the Orion?
SQL: SELECT AVG("number_of_s_eva") FROM apollo_11_moon_landing WHERE "lunar_lander" = 'orion'