00283nam a2200121Ia 4500008004100000100002100041245003200062260002300094300000800117650001200125942000700137999001700144190216s9999||||xx |||||||||||||| ||und||  aHerbert Friedman 0aPractical Low Cost Projects  bHoward Wsamsc1975  a95p  aPhysics  cBK  c33085d33085