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Using the last object selected, the object with the solid color grab handles, makes the selected objects the same size in the dimension you select. The color of the grab handles is based on the color you set from Selected Items on the Appearance tab of the Display Properties dialog box in the Control Panel.
Width
Adjusts width.
Toolbar shortcut: .
Height
Adjusts height.
Toolbar shortcut: 
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Both
Adjusts both the width and the height.
Toolbar shortcut: 
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