Consider the following tables (relations):

Students:

Roll-No	Name
18CS101	Ramesh
18CS102	Mukesh
18CS103	Ramesh

Performance:

Roll-No	Course	Marks
18CS101	DBMS	60
18CS101	Compiler Design	65
18CS102	DBMS	80
18CS103	DBMS	85
18CS102	Compiler Design	75
18CS103	Operating System	70

Primary keys in the tables are shown using Underline. Now, Consider the following query:

SELECT S.Name, Sum (P.Marks)

FROM Students S, Performance P

WHERE S.Roll-No = P.Roll-No

GROUP BY S.Name

The number of rows returned by the above query is