You use Microsoft .NET Framework 4 to create a Windows Presentation Foundation (WPF) application. The application contains a form named frmMain that contains a button named btnSave. You create a ProgressBar control named saveProgress. Initially, saveProgress is not displayed on frmMain. When a user clicks btnSave, you have the following requirements: saveProgress is slightly visible after 0.2 seconds saveProgress is fully visible after 1 second You need to declare the corresponding storyboard. You write the following code fragment. (Line numbers are included for reference only.) Which code fragment should you insert at line 02 to complete the declaration?（）

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