Click Cavity Extraction
.
The Extract Cavity dialog box appears.
Select Body.1 as the source body.
Click the Extract behavior drop-down list
and select Extraction Properties.1.
Click OK to confirm.
Click External Feature
.
Select Sketch.7 as the Profile/Surface.
Click the Reverse direction button.
Set the First Length to 100.
Click OK to confirm.
Right-click Body.1 and select Hide/Show.
Right-click PartBody and select Hide/Show.