Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_48 (frequency___hz__ INTEGER, helmholtz_pitch VARCHAR)
### Question:
What is the lowest Frequency where the Hemholtz pitch is d?
### Answer:
SELECT MIN(frequency___hz__) FROM table_name_48 WHERE helmholtz_pitch = "d"