please help both parts please thank you so much

Consider the database consisting of the following relations: ProjectGroup(group id, group_name, number_of_members) Student(student id, student_name, gender, phone) Assigned(student id, group id, date) In case you cannot type the usual RA Greek Ietters easily, you should use the tollowing convention. Operator parameters should be enclosed in square brackets. Write down the Relation Algebra (RA) expressions for the following queries: a) Find the id of the students who have not been assigned to any project group yet. b) Find the id and name of all female students who have been assigned to a group named "The dreamers