To Copy All Items on a Layer
1. Click 
or in the Model Tree navigator window click 
and then click Layer Tree on the list. The Layer Tree opens.
or in the Model Tree navigator window click and then click Layer Tree on the list. The Layer Tree opens.2. Right-click the layer whose contents you want to copy. The shortcut menu appears.
3. Click Select Items.
4. Click Copy Item. The contents of the selected layer are copied to the clipboard.
5. Select the layer on which you want to paste the copied items, or create a new layer by clicking and then clicking New Layer.
and then clicking New Layer.6. Click and then click Paste. The items are copied onto the selected layer.
and then click Paste. The items are copied onto the selected layer.