function funqa3301() {
  var nq = 12;
  var ok=1;
  var si="";
  var jj=0;
  var bb=new Array(12);
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  if (jj==1) {bb[0]=true;}
  if (jj==2) {bb[0]=false;}
  jj=document.qa3301.qa02.selectedIndex;
  if (jj==0) {ok=0;}
  if (jj==1) {bb[1]=true;}
  if (jj==2) {bb[1]=false;}
  jj=document.qa3301.qa03.selectedIndex;
  if (jj==0) {ok=0;}
  if (jj==1) {bb[2]=true;}
  if (jj==2) {bb[2]=false;}
  jj=document.qa3301.qa04.selectedIndex;
  if (jj==0) {ok=0;}
  if (jj==1) {bb[3]=true;}
  if (jj==2) {bb[3]=false;}
  jj=document.qa3301.qa05.selectedIndex;
  if (jj==0) {ok=0;}
  if (jj==1) {bb[4]=true;}
  if (jj==2) {bb[4]=false;}
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  if (jj==0) {ok=0;}
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  if (jj==2) {bb[5]=false;}
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  if (jj==0) {ok=0;}
  if (jj==1) {bb[6]=true;}
  if (jj==2) {bb[6]=false;}
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  if (jj==0) {ok=0;}
  if (jj==1) {bb[7]=true;}
  if (jj==2) {bb[7]=false;}
  jj=document.qa3301.qa09.selectedIndex;
  if (jj==0) {ok=0;}
  if (jj==1) {bb[8]=true;}
  if (jj==2) {bb[8]=false;}
  jj=document.qa3301.qa10.selectedIndex;
  if (jj==0) {ok=0;}
  if (jj==1) {bb[9]=true;}
  if (jj==2) {bb[9]=false;}
  jj=document.qa3301.qa11.selectedIndex;
  if (jj==0) {ok=0;}
  if (jj==1) {bb[10]=true;}
  if (jj==2) {bb[10]=false;}
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  if (jj==2) {bb[11]=false;}
  if (ok==0) {alert("Some responses are missing.\nPlease select TRUE or FALSE\nfor all statements.")}
  else {
    var ok=0;
    var aa=new Array(true,false,true,false,false,false,true,false,true,false,true,false);
    var sx="width=450,height=200,resizable=yes,scrollbars=yes";
    var w = window.open("","qa3301w",sx,replace=true);
    if (aa[0]!=bb[0]) {
      w.document.write('<font size=+2 color="#aa0000">#1 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#1 Correct!<br>');ok++;
    }
    w.document.write("Satellites orbiting around the Earth have the minimum speed (typically 17,000 mph) needed to stay in orbit and not impact on Earth.  The satellites orbit without any propulsion.  They are constantly pulled down by the Earth's gravity but because of their high speed along the orbit (at a right angle to gravity), satellites do not hit the Earth.  Their inertia keeps them moving and the force of Earth's gravity bends their path around the Earth.");
    w.document.write("<p>");
    if (aa[1]!=bb[1]) {
      w.document.write('<font size=+2 color="#aa0000">#2 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#2 Correct!<br>');ok++;
    }
    w.document.write("Some satellites depend on reflected solar energy to gather data and so can only work during the day.  Others measure thermal radiation of objects and substances or generate their own radar or laser radiation.  These satellites do not need the Sun's radiation and can collect data at night.");
    w.document.write("<p>");
    if (aa[2]!=bb[2]) {
      w.document.write('<font size=+2 color="#aa0000">#3 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#3 Correct!<br>');ok++;
    }
    w.document.write("Once in orbit, travelling at high speed, satellites do not need fuel to keep traveling.  Newton said: Objects in motion tend to stay in motion.  The Earth pulls satellites downwards at right angles to the orbit.  This does not slow up the satellite and it will continue orbiting until friction with the low density atmosphere causes it to slow down and leave orbit.");
    w.document.write("<p>");
    if (aa[3]!=bb[3]) {
      w.document.write('<font size=+2 color="#aa0000">#4 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#4 Correct!<br>');ok++;
    }
    w.document.write("Some wavelengths of electromagnetic radiation measured by satellites (radar, microwave) passes through clouds.  Clouds do block visible radiation that is seen by our eyes.  For example, pilots in airplanes abov the clouds communicate using emectromagnetic waves with the correct wavelength to easily pass through the clouds.");
    w.document.write("<p>");
    if (aa[4]!=bb[4]) {
      w.document.write('<font size=+2 color="#aa0000">#5 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#5 Correct!<br>');ok++;
    }
    w.document.write("Everyday, a large fraction of the Earth's surface is covered by clouds.  The images that NASA provides are typically a composite image built from many images using data collected over several days or weeks");
    w.document.write("<p>");
    if (aa[5]!=bb[5]) {
      w.document.write('<font size=+2 color="#aa0000">#6 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#6 Correct!<br>');ok++;
    }
    w.document.write("Some satellites measure reflected solar, laser or radar energy or emitted thermal radiation coming from the Earth.  It is important to study many different wavelengths of radiation because each wavelength can provide more information about conditions of the surface that emitted or reflected the radiation.");
    w.document.write("<p>");
    if (aa[6]!=bb[6]) {
      w.document.write('<font size=+2 color="#aa0000">#7 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#7 Correct!<br>');ok++;
    }
    w.document.write("The invisible radiation can be very useful to measure the Earth's surface environment.  Invisible radiation like thermal infrared radiation can tell us about the temperature of a substance or object.  A hot or a cool kitchen pot or heating surface looks the same to our eyes but emit very different amounts of infrared radiation.");
    w.document.write("<p>");
    if (aa[7]!=bb[7]) {
      w.document.write('<font size=+2 color="#aa0000">#8 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#8 Correct!<br>');ok++;
    }
    w.document.write("If all satellites were placed that far away, it would be hard to distinguish changes that happen on a small scale.  Most Earth-observing satellites orbit close to the earth and each image collected covers only a small region of the Earth's surface.");
    w.document.write("<p>");
    if (aa[8]!=bb[8]) {
      w.document.write('<font size=+2 color="#aa0000">#9 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#9 Correct!<br>');ok++;
    }
    w.document.write("Once in orbit, satellites do not have the fuel or propulsion necessary to change their orbit.  Most collecting data over all the Earth will orbit the over the Poles.  As the Earth slowly rotates, the satellite will observe a different regions on the surface after each 90 minute orbit.");
    w.document.write("<p>");
    if (aa[9]!=bb[9]) {
      w.document.write('<font size=+2 color="#aa0000">#10 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#10 Correct!<br>');ok++;
    }
    w.document.write("To proved continuous service to a city from a single satellite, the satellite has to stay above the same location on Earth all the time.  The only way to accomplish that is to orbit around the Equator with an orbital period of 24 hours (matched to the Earth rotation period).  This orbit is called a geosynchronous orbit.");
    w.document.write("<p>");
    if (aa[10]!=bb[10]) {
      w.document.write('<font size=+2 color="#aa0000">#11 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#11 Correct!<br>');ok++;
    }
    w.document.write("Solar power is preferred since there are no clouds in space and solar power is a simple, dependable, easily engineered source of energy.");
    w.document.write("<p>");
    if (aa[11]!=bb[11]) {
      w.document.write('<font size=+2 color="#aa0000">#12 Wrong!<br>');
    } else {
      w.document.write('<font size=+2 color="#000000">#12 Correct!<br>');ok++;
    }
    w.document.write("Satellites do not require power to stay in orbit.  Satellites are given a high speed so that their inertia keeps them orbiting.");
    w.document.write("<p>");
    document.qa3301.qscore.value=Math.floor(100.0*ok/nq);
  }
}