div class=ts-pagebuttonPage 1button div class=ts-image a href=https:reader042vdocumentsmxreader042viewer20220307145afddd417f8b9a944d8e0c65html5page1jpg target=_blank amp-img class=ts-thumb alt=Page 1: sciencenetlinkscomsciencenetlinkscommediafiler20110927tf-snl-balancing-pointspdfThe best mobiles have parts that are balanced and move freely If the parts arent balanced src=https:reader042vdocumentsmxreader042viewer20220307145afddd417f8b9a944d8e0c65html5thumbnails1jpg width=142 height=106 layout=responsive amp-imga divdiv