What are the different ways to invoke an application using QTP?

a)SystemUtil.Run
SystemUtil.Run (Filename, Parameters, Path, Operation )
Example: SystemUtil.Run(“iexplorer.exe”,http://www.gmail.com)

b) InvokeApplication
Example: InvokeApplication “C:\Program Files\Internet Explorer\IEXPLORE.EXE http://www.gmail.com”

c) Creating a shell object using VB Script
Example: Create a “WScript.shell” object.
Dim testshell