Three of the drill holes have small countersinks that can be machined in a single Drill operation using a countersink tool.
Drilling panel
Drill
.
button.
to close the Tool Library dialog. 
The countersunk faces of the other two holes are automatically selected since they are identical to the first
at the bottom of the Operation dialog box, or right-click in the graphics window and select OK from the marking menu, to automatically start calculating the toolpath. The toolpath should appear as shown in the following image:

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