DEAR MISS MANNERS: I was being waited on at a copy center. I’m 82 years old. While talking with the clerk about my order, a young 20-something blond walked up next to me and told him she was there to pick up her order. The clerk stopped waiting on me and attended to the young blond. I was very angry and I told the clerk that I didn’t appreciate being dropped to wait on a line-jumper. His response was that he was multitasking. I stayed long enough to complete my transaction and let him know that I would no longer do any business there. GENTLE READER: Please excuse Miss Manners for finding your …