CREATE TABLE table_10718984_2 (no_in_season INTEGER, written_by VARCHAR(255), us_viewers__millions_ VARCHAR(255))
What is the number in the season that Marlene Meyer wrote and 20.49 million people watched?
    
SQL: SELECT MAX(no_in_season) FROM table_10718984_2 WHERE written_by = "Marlene Meyer" AND us_viewers__millions_ = "20.49"