function calc_post1(){
  if(!form.postcard1.checked){
     newtotal = parseFloat(document.form.x_amount.value) - parseFloat(6.95);
  }
  if(form.postcard1.checked){
     newtotal = parseFloat(document.form.x_amount.value) + parseFloat(6.95);
  }
  document.form.x_amount.value = parseFloat(newtotal).toFixed(2);
}
function calc_cert1(){
  if(!form.certificate1.checked){
     newtotal = parseFloat(document.form.x_amount.value) - parseFloat(8.95);
  }
  if(form.certificate1.checked){
     newtotal = parseFloat(document.form.x_amount.value) + parseFloat(8.95);
  }
  document.form.x_amount.value = parseFloat(newtotal).toFixed(2);
}



function calc_post2(){
  if(!form.postcard2.checked){
     newtotal = parseFloat(document.form.x_amount.value) - parseFloat(6.95);
  }
  if(form.postcard2.checked){
     newtotal = parseFloat(document.form.x_amount.value) + parseFloat(6.95);
  }
  document.form.x_amount.value = parseFloat(newtotal).toFixed(2);
}
function calc_cert2(){
  if(!form.certificate2.checked){
     newtotal = parseFloat(document.form.x_amount.value) - parseFloat(8.95);
  }
  if(form.certificate2.checked){
     newtotal = parseFloat(document.form.x_amount.value) + parseFloat(8.95);
  }
  document.form.x_amount.value = parseFloat(newtotal).toFixed(2);
}



function calc_post3(){
  if(!form.postcard3.checked){
     newtotal = parseFloat(document.form.x_amount.value) - parseFloat(6.95);
  }
  if(form.postcard3.checked){
     newtotal = parseFloat(document.form.x_amount.value) + parseFloat(6.95);
  }
  document.form.x_amount.value = parseFloat(newtotal).toFixed(2);
}
function calc_cert3(){
  if(!form.certificate3.checked){
     newtotal = parseFloat(document.form.x_amount.value) - parseFloat(8.95);
  }
  if(form.certificate3.checked){
     newtotal = parseFloat(document.form.x_amount.value) + parseFloat(8.95);
  }
  document.form.x_amount.value = parseFloat(newtotal).toFixed(2);
}



function calc_post4(){
  if(!form.postcard4.checked){
     newtotal = parseFloat(document.form.x_amount.value) - parseFloat(6.95);
  }
  if(form.postcard4.checked){
     newtotal = parseFloat(document.form.x_amount.value) + parseFloat(6.95);
  }
  document.form.x_amount.value = parseFloat(newtotal).toFixed(2);
}
function calc_cert4(){
  if(!form.certificate4.checked){
     newtotal = parseFloat(document.form.x_amount.value) - parseFloat(8.95);
  }
  if(form.certificate4.checked){
     newtotal = parseFloat(document.form.x_amount.value) + parseFloat(8.95);
  }
  document.form.x_amount.value = parseFloat(newtotal).toFixed(2);
}