Given the following relational schemas of a Hospital database, express the queries using Relational Algebra. Hospital Database Doctor (Doc_id, Name, Designation, Area_of_Expertise) Employee (Emp_id, Phone, DoB, Office_Room, Address, Salary, Gender) Patient (Pat_id, Name, DoB, Address, Gender) Patient History (Pat_id, Problem_Area) Sees (Pat_id, Doc_id, Date) List the names of all the doctors and their area of expertise. Find the names of doctors with annual salary > 150k. List the patients (names and ids) of doctor “Johnson”. List the female patients treated by female doctors. Find the staffs information that are not doctor. Find all the doctors names and their area of expertise seen by a patient with Pat_id = “P_1110000” Find all the patients name and gender who are diagnosed/treated for “Cancer”. Find the office (room number) of doctor “Smith” who is an expert in “Diabetes & Obesity”. Find all the doctors, staffs, and patients name along with id and address. If the hospital is expanded to more than one building, how will you adjust the information in this hospital database?