var fDesc=new Array(); fDesc[0] = "These are comprehensive physics textbooks. They include text, illustrations, animations, simulations and homework problems. The table of contents provides one way for you to survey the topics covered.
There are three different levels of textbooks available, from a non-calculus textbook to a calculus-based textbook for science/engineering majors."; function tShowHide(id, show) { var s = document.getElementById("desc"); if ((s.innerHTML.length<=212 || show==1) && show!=2) { s.innerHTML = fDesc[id]; if (document.getElementById('m1')) document.getElementById('m1').style.display='none'; if (document.getElementById('m2')) document.getElementById('m2').style.display='none'; if (document.getElementById('more_txt')) document.getElementById('more_txt').style.display='inline'; } else { s.innerHTML = ''; } }