/**
  * get suggested questions ids
  * @param object $a_usr_id
  * @param object $a_crs_id
  * @return 
  */
 public static function getSuggestedQuestions($a_usr_id, $a_crs_id)
 {
     foreach (self::_getSuggested($a_usr_id, $a_crs_id) as $objective_id) {
         include_once './Modules/Course/classes/class.ilCourseObjectiveQuestion.php';
         $obj = new ilCourseObjectiveQuestion($objective_id);
         foreach ($obj->getFinalTestQuestions() as $qst) {
             $qsts[] = $qst['question_id'];
         }
     }
     return $qsts ? $qsts : array();
 }