How mutch will my daughter get for her survivor benefits?

Her daddy just passed...he has worked off and on all his life..he was 40..but I know some of his jobs were under the table..some were not...At the time of his death..he was drawing unemployment..my daughter is 14 now..was just wondering how mutch she will get?..Plus..we were only married 3 years..the social security sight said a divorced partner can get benefits also if they have the child to the parent that passed..but the lady told me I would have had to been married to him 10 years...and also be 60..I need to know all this as i am raising this child alone and finances are VERY VERY tight...Pleas Help