Database table by name Overtime_allowance is given below:

Employee	Department	OT_allowance
RAMA	Mechanical	5000
GOPI	Electrical	2000
SINDHU	Computer	4000
MAHESH	Civil	1500

What is the output of the following SQL query?

select count(*) from

((select Employee, Department from Overtime_allowance) as S

natural join (select Department, OT_allowance from Overtime_allowance)

as T);