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_6 (proposed VARCHAR, listed VARCHAR, county VARCHAR)
### Question:
When was the site listed 03/31/1989 in rockingham county proposed?
### Answer:
SELECT proposed FROM table_name_6 WHERE listed = "03/31/1989" AND county = "rockingham"