CREATE TABLE weather (zip_code VARCHAR, mean_sea_level_pressure_inches INT)

What is the zip code in which the average mean sea level pressure is the lowest?
SELECT zip_code FROM weather GROUP BY zip_code ORDER BY AVG(mean_sea_level_pressure_inches) LIMIT 1
SELECT "zip_code" FROM "weather" GROUP BY "zip_code" ORDER BY AVG("mean_sea_level_pressure_inches") NULLS FIRST LIMIT 1