function valid(){
a = document.frm;
if(a.txtname.value==""){
alert("Please enter your Name");
a.txtname.focus();
a.txtname.select();
return false;
}
if(a.txttelno.value==""){
alert("Please enter your telephone number");
a.txttelno.focus();
a.txttelno.select();
return false;
}
if(a.txtemail.value==""){
alert("Please enter your Email");
a.txtemail.focus();
a.txtemail.select();
return false;
}
else
{
	var emailfilter=/^\w+[\+\.\w-]*@([\w-]+\.)*\w+[\w-]*\.([a-z]{2,4}|\d+)$/i
	var returnval=emailfilter.test(document.frm.txtemail.value)
	if (returnval==false){
		alert("Please enter a valid email address")
		document.frm.txtemail.select()
		return false;
}
}
if(a.txtaddr.value==""){
alert("Please enter your contact address");
a.txtaddr.focus();
a.txtaddr.select();
return false;
}
if(a.txtadlt.value==""){
alert("Please enter number of adults");
a.txtadlt.focus();
a.txtadlt.select();
return false;
}
if(a.txtchild.value==""){
alert("Please enter number of children");
a.txtchild.focus();
a.txtchild.select();
return false;
}
if(a.txtadlt.value==""){
alert("Please enter number of adults");
a.txtadlt.focus();
a.txtadlt.select();
return false;
}
if(a.txtbooster.value==""){
alert("Please enter booster seat required ");
a.txtbooster.focus();
a.txtbooster.select();
return false;
}
if(a.txtpickaddr.value==""){
alert("Please enter pick-up address");
a.txtpickaddr.focus();
a.txtpickaddr.select();
return false;
}
if(a.txtdestaddr.value==""){
alert("Please enter destination address");
a.txtdestaddr.focus();
a.txtdestaddr.select();
return false;
}
if(a.txtairport.value==""){
alert("Please enter airport terminal");
a.txtairport.focus();
a.txtairport.select();
return false;
}
return;
}