An envelope <a href=" http://www.prodental.com/?gregory-g-mario-taxis-pharmaceuticals-inc ">best drugstore bronzer for light skin</a> hypothesis: It could be less risky to use cell phones while on a highway than to use them on other roads (highways tend to be divided, and while cars are moving faster they are moving in the same direction and there are no traffic intersections, so there are fewer interruptions/other things you need to pay attention to).