Invalid argument supplied for foreach() on line 538 and Division by zero on line 545

warning: Invalid argument supplied for foreach() in /home/user/example.com/sites/all/modules/og_node_approval/og_node_approval.module on line 538.
warning: Division by zero in /home/user/example.com/sites/all/modules/og_node_approval/og_node_approval.module on line 545.