Who gets paid every other year according to Apple payroll policies? If your friend never officially interviewed with Apple-badged employees on multiple occasions, then this email attachment is a dubious scam.
In Apple Mail : View menu : Message : All Header — in the text result, look for the line that begins with Return-Path, or Return-path. You are interested in the address between < >. If @apple.com> or @something.apple.com> does not appear here, it is spam.