I felt confuse about whom n whose.pls u explain with me..tks

Whom and Whose is different world different meanings. Question 1)That's the man _____ son is a singer ? Ans.whose. Question 2)I have got friend _____ Father is a writer ? Ans.Whose. Question 3) They lawyer _____ I met, advised me to go to court ? Ans.whom. whom is use formal english (people )