Example 1:
After creating the function copy this into your Query Pane
SELECT
dbo.Is_Leap (1800) AS [1800],
dbo.Is_Leap (1900) AS [1900],
dbo.Is_Leap (2000) AS [2000],
dbo.Is_Leap (2004) AS [2004],
dbo.Is_Leap (2008) AS [2008]
Example 2:
After creating the function copy this into your Query Pane
Print dbo.Is_Leap (2009)