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_20 (us_cash_box VARCHAR, year VARCHAR, us_billboard VARCHAR)

### Question ###
What is the US cash box before 1978 with a US billboard of 35?

### Accurate SQL ###

SELECT us_cash_box FROM table_name_20 WHERE year < 1978 AND us_billboard = 35