SQL: Get Distance from 2 Lat-Long pairs.

Declare @T1 GEOGRAPHY,@T2 GEOGRAPHY;
Select @T1= GEOGRAPHY::Point('42.372', '-71.0298', 4326) --Boston
,@T2=GEOGRAPHY::Point('41.953', '-87.643', 4326) --Chicago
Select @T1.STDistance(@T2) As 'Distane in Meters' ,@T1.STDistance(@T2) / 1000 As 'Distane in KM'