How to Find 3th Highest Salary In Sql Server 2008

First create Table ----
--CREATE TABLE ED(ecode INT,ename VARCHAR(10),edept VARCHAR(10))
--CREATE TABLE ES(ecode INT,Esal INT ,eSaltype VARCHAR(10))

then Enter the Value 
--INSERT INTO ED( ecode, ename, edept)VALUES(1,'virendra','it')
--INSERT INTO ED( ecode, ename, edept)VALUES(2,'Ajit','mgt')
--INSERT INTO ED( ecode, ename, edept)VALUES(3,'pavan','it')
--INSERT INTO ED( ecode, ename, edept)VALUES(4,'kuldeep','mgt')
--INSERT INTO ES( ecode, Esal, eSaltype)VALUES(1,3000,'basic')
--INSERT INTO ES( ecode, Esal, eSaltype)VALUES(1,3000,'basic')
--INSERT INTO ES( ecode, Esal, eSaltype)VALUES(1,1000,'insetive')
--INSERT INTO ES( ecode, Esal, eSaltype)VALUES(2,5000,'basic')
--INSERT INTO ES( ecode, Esal, eSaltype)VALUES(2,3000,'bounse')
--INSERT INTO ES( ecode, Esal, eSaltype)VALUES(3,7000,'basic')
--INSERT INTO ES( ecode, Esal, eSaltype)VALUES(3,3000,'bounse')
--INSERT INTO ES( ecode, Esal, eSaltype)VALUES(3,8000,'intsetive')

then After Create the Query to Find Any Highest Salary

SELECT a.[ecode] Code,a.[ename] Name,SUM(b.[Esal]) Salary FROM [MyDataDb].[dbo].[ED] AS a INNER JOIN [MyDataDb].[dbo].[ES] AS B ON b.ecode=a.ecode GROUP BY a.edept,a.ecode,a.ename

SELECT Salary,Name,ROW_NUMBER() OVER (ORDER BY Salary DESC) AS RN FROM  
( SELECT a.[ecode] Code,a.[ename] Name,SUM(b.[Esal]) Salary FROM [MyDataDb].[dbo].[ED] AS a INNER JOIN [MyDataDb].[dbo].[ES] AS B ON b.ecode=a.ecode GROUP BY a.edept,a.ecode,a.ename)a

SELECT Salary,Name FROM (SELECT Salary,Name,ROW_NUMBER() OVER (ORDER BY Salary DESC) AS RN FROM  

( SELECT a.[ecode] Code,a.[ename] Name,SUM(b.[Esal]) Salary FROM [MyDataDb].[dbo].[ED] AS a INNER JOIN [MyDataDb].[dbo].[ES] AS B ON b.ecode=a.ecode GROUP BY a.edept,a.ecode,a.ename)a )c WHERE c.RN=2