Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_69 (yield VARCHAR, purpose VARCHAR, location VARCHAR)

### Question ###
What is the yield in NTS Area U2R when the purpose is weapons development?

### Accurate SQL ###

SELECT yield FROM table_name_69 WHERE purpose = "weapons development" AND location = "nts area u2r"