Table schema:
CREATE TABLE table_2150068_1 (launch_date__utc_ VARCHAR, diameter_m_ VARCHAR, usage VARCHAR, mass_kg_ VARCHAR)

Question: What was the launch date for the sattelite with ado that was 4 kg and 3 meters in diameter?
SQL: SELECT launch_date__utc_ FROM table_2150068_1 WHERE usage = "ado" AND mass_kg_ = "4" AND diameter_m_ = "3"