EASYGoes up and down.Gets wet, no doubt.No good to youWhen inside-out.ANSWER: An umbrellaAn umbrella opens and closes, going up and down. When used, it gets wet -- unless it's uselessly turned inside-out.INTERMEDIATEMulti-purpose by no small stretch.A missle. Small-scale tourniquet.Hair-do helper. Organizer.Hand-held musical instrument.ANSWER: A rubberbandA stretchy rubberband has many uses. It's often fired as a tiny missle, and could be used as a tourniquet to staunch any leak. Many have helped keep pony-tails in place and have served as desktop organizers. And, of course, a rubberband held between two outstretched fingers can be melodically strummed.DIFFICULTSurface smoothed by frequent traffic.Gendered entrance (but both may go).Metal door rests on no hinges.Goes deep to places few will know.ANSWER: A manholeThe manhole cover is smoothed by many cars and trucks. Although it is called a "man"hole, women may enter through it. Though it is a metal door, a manhole lacks hinges. The manhole leads to subterranean places where few people ever go.