i want just number 4

Exercises 11.6 GenD p?q?:P cas!:P cas! = { 1. Specify an operation to return the set of all people who have any one of the following relationships to a given person x?. The name of the required relationship should be an input to the operation, (1) The parents of person x? (ii) The grandparents of person x? (iii) The grandchildren of person x? (iv) The descendants of person x? (v) The siblings of person x? (vi) The aunts of person x? 2. Give a Z expression for the set of all people in the database who have no relatives in the database. 3. Give a Z expression for the set of all people in the database who have no siblings in the database. 4. Specify an operation to output the number of generations through which melyen individual p can trace his/her family history in the database, Note that people is a is the perso therefore p on PERSC own ancest