10 points) Single underline a primary key, double underline every foreign key, and cycle every candidate key for the following relations. A staff of a doctor can alos be a patient An employee can not be a staff and a doctor at the same time. A patient does not have to be a US citizen. A patient cannot be admitted twice at any date. The driverno is the driver license number and ssno is the social security number. Any assumption has to be logical and realistic without changing the problem. (Minus 1 point for each wrong answer) Patient (patno, name, add, ssno, driverno) Staff (staffno, name, add, ssno, driverno) Doctor (docno, name, add, ssno, driverno) Admission (roomno, patno, startdate, enddate, staffno) Room (roomno, type, fee) Drug (drugno, drugname, drugsalesprice, drugprice) Prescription (prescno, docno, patno, drugno, stardate, enddate) 12. Given the following relations: Patient (patno, name, add, ssno, driverno) Staff (staffno, name, add, ssno driverno) Doctor (docno, name, add, ssno, driverno) Admission (roomno, patno, startdate, enddate, staffno) Room (roomno, type, fee) Drug (drugno, drugname, drugsalesprice, drugprice) Prescription (prescno, docno, patno, drugno, stardate, enddate) Formulate the following queries in relational algebra. (a) (13 points) What is the total fee collected from each room type during January 2020. The report should have type and total fee.