CREATE TABLE table_10408617_5 (prefixes VARCHAR(255), scheme VARCHAR(255), approx_premium VARCHAR(255))
What prefixes are priced at pence per minute, fixed at all times with a premium of 3p/min?
    
SQL: SELECT prefixes FROM table_10408617_5 WHERE scheme = "Pence per minute, fixed at all times" AND approx_premium = "3p/min"