CREATE TABLE table_77930 ("String" CLOB, "Scientific pitch" CLOB, "Helmholtz pitch" CLOB, "Interval from middle C" CLOB, "Frequency  (  Hz  ) " FLOAT)

What is the lowest Frequency where the Hemholtz pitch is d?
SELECT MIN("Frequency ( Hz )") FROM table_77930 WHERE "Helmholtz pitch" = 'd'
SELECT MIN("Frequency ( Hz )") FROM "table_77930" WHERE "Helmholtz pitch" = 'd'