Notice: Undefined variable: kgroup_session in E:\xampp\htdocs\teacher2\m\inc\kgroup.php on line 2

Notice: Undefined variable: kgroup_session in E:\xampp\htdocs\teacher2\m\inc\kgroup.php on line 9

Notice: Undefined variable: kgroup_session in E:\xampp\htdocs\teacher2\m\inc\kgroup.php on line 16

Fatal error: Uncaught Error: Call to undefined function mysql_query() in E:\xampp\htdocs\teacher2\m\inc\kgroup.php:25 Stack trace: #0 {main} thrown in E:\xampp\htdocs\teacher2\m\inc\kgroup.php on line 25