To specify bubble shadow edge and fill attributes:
In the Callout Preferences dialog box click Shadow Settings, or in the Object Info palette for a selected callout or keynote legend, click Bubble Shadow Settings.
To activate this option, Bubble Style must be set to a style other than None, Bracket, ISO, or Vertical Accent Bar, and Bubble Shadow must be selected.
The Bubble Shadow Settings dialog box opens.
Click to show/hide the parameters.
Specify the desired parameters and click OK.
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