QCM questons 30

Warning: Undefined property: stdClass::$username in /home/moodle/www/moodle-test3/lib/classes/output/user_picture.php on line 295

Deprecated: explode(): Passing null to parameter #2 ($string) of type string is deprecated in /home/moodle/www/moodle-test3/lib/classes/output/user_picture.php on line 295

Warning: Undefined array key 1 in /home/moodle/www/moodle-test3/lib/classes/output/user_picture.php on line 295

Deprecated: strstr(): Passing null to parameter #1 ($haystack) of type string is deprecated in /home/moodle/www/moodle-test3/lib/classes/output/user_picture.php on line 295

Warning: Undefined property: stdClass::$username in /home/moodle/www/moodle-test3/lib/classes/output/user_picture.php on line 295

Deprecated: explode(): Passing null to parameter #2 ($string) of type string is deprecated in /home/moodle/www/moodle-test3/lib/classes/output/user_picture.php on line 295

Warning: Undefined array key 1 in /home/moodle/www/moodle-test3/lib/classes/output/user_picture.php on line 295

Deprecated: strstr(): Passing null to parameter #1 ($haystack) of type string is deprecated in /home/moodle/www/moodle-test3/lib/classes/output/user_picture.php on line 295