If you had designed this rear cover, what are 5 tests that you would conduct on the completed iPod Touch assembly to ensure that your rear cover design met all applicable requirements? Why?

Background: The interviewer set the rear cover of an old iPod Touch on the table and asked me to identify the materials. If you had designed this rear cover, what are 5 tests that you would conduct on the completed iPod Touch assembly to ensure that your rear cover design met all applicable requirements? Why?