[ESSN, Pno] is a candidate key. The primary key could be a composite key [ESSN, Pno].
Functional dependencies:
fd1: ESSN, Pno -> hours
fd2: ESSN -> fName, IName
fd3: Pno -> Pnumber, Pname, Plocation
Second normal form (in the format of relational schema):
R1(ESSN, Pno, hours)
R2(SSN, fName, IName)
R3(Pnumber, Pname, Plocation)
Third normal form:
R1(ESSN, Pno, hours)
R2(SSN, fName, IName)
R3(Pnumber, Pname)
R4(Pnumber, Plocation)