How to re-target unit-tests to .Net Framework 3.5 in VS 2010 SP1

Visual Studio 2010 Service Pack 1 enables basic support for unit tests that target .Net framework 3.5.  With this support the users can:Create new unit-test projects and target them to the .NET Framework 3.5. Upgrade VS 2008 unit-test projects to VS 2010 SP1 and then re-target them to .NET Framework 3.5Run unit tests that target the .NET Framework 3.5 from Visual Studio 2010 SP1 on your local