1. Airplane travelers note that their cosmetics bottles and other containers have leaked during flight. What m

I've never had that problem, maybe the people who've had leakage problems used bad bottles or didn't secure them well. You need to put all your liquids in a plastic bag anyhow, so if they do leak, it shouldn't be too much of a problem. Airplanes do have pressurized cabins which can affect certain types of bottles, but normally it shouldn't be a problem.