CREATE TABLE table_21012786_2 (length_weight_of_missile VARCHAR, diameter_of_torsion_spring VARCHAR)

When the torsion spring diameter is 38.4cm what would be the length or weight of the missile
SELECT length_weight_of_missile FROM table_21012786_2 WHERE diameter_of_torsion_spring = "38.4cm"
SELECT "length_weight_of_missile" FROM "table_21012786_2" WHERE "38.4cm" = "diameter_of_torsion_spring"