Código PHP:
$persona = $_POST['personas'];
include "conectar.php";
$result = mysql_query("SELECT * FROM entrega_tarjeta WHERE persona='".$persona."'");
$rows=mysql_num_rows($result)-1;
$fec=mysql_result($result,0,"fechasol");
$fec1=$_POST['fechasol'];
$fec2 = mktime($fec1);
$fec3 = mktime($fec);
$fec4 = abs($fec2 - $fec3);
$fec5 = date($fec4/3600);
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