High school senior: I still don't understand why the math teacher insisted that our class learn triggernometry --- I'm a staunch pacifist, so I don't even like guns; why the heck do I need to learn about 'em if the subject will never even come up in my ordinary daily life??
A sunburn or suntan focused on the left arm. It is caused by the left side of the body being the only half that gets exposed to sunlight while driving. Presumably, it would be located on the right side of the body in countries where they drive on the left side of the road.